2013 Petzl Croll & Basic review

I’m a self confessed gear junky. I love to play with shiny things and we all love a rope trick or two. I also like looking good when I work, image is important as a first impression can be the difference between a days work and no work. All vanities aside, I think that a professional instructor should be equipped with the most up to date equipment available and of course the knowledge of how to use it! You can imagine how excited I was to read that Petzl were planning a re-release of the Croll and Basic early 2013. I was also mildly worried as historically there had been little change to the design of what was arguably an already excellently functional pair of products.
I managed to get my hands on one of the new Croll ascenders as they hit the shelves and have just acquired a new Basic literally as Hitch N Hike unpacked their shipment from Lyon.
I’ll start with a look at the Croll.

2013 Petzl Croll


Like the Basic, the last major design change in the Croll was when they went over to plastic safety catches from the metal ones. Since then we’ve only seen some small cosmetic tweaks. As you can see above the the 2013 Croll (right) is a complete redesign on the previous model. It looks as though Petzl have done a ground up redesign with a completely new set of parts and with an eye on size and weight.

The previous versions of the Croll weighed in at 130g, the 2013 is a featherweight 90g.
Usefully, the 2013 Croll is small enough to stir your coffee with if you are unable to find a spoon nearby.


The safety catch although small is easy to operate, one handed installation and removal from the rope is just as easy and smooth as prior versions. With the cam being smaller a shorter action is required to disengage the safety catch making the process faster but in no way less secure.
The attachment holes are well sited and allow the Croll to sit flat. I have used mine with a Torse chest harness and found they make a perfect combination, as I’d expect from 2 products from the same manufacturer. I’d recently had issues with an Anthron AC-30 chest ascender as the use of a Torse interfered with the clean running of the rope.
The main change apart from size is the addition of a stainless steel plate inside the rope groove. Although it does not cover the entire rope contact surface it shields the frontal portion where most heavy wear is generated as the user leans back on ascent. The stainless steel insert should improve the lifetime of the 2013 Croll, especially for cavers operating in digs or where there are a lot of fixed, gritty ropes.

I had a test of the Croll down Oxlow Mine recently and we used a mix of rope types and diameters, some very supple and some stiff and fat. After the initial bit of step and pull, the rope runs as smoothly through the Croll as it ever did, with no twisting or feeding issues.

In summary then, in producing the 2013 Croll, Petzl has taken a much loved and hugely popular item of equipment and completely redesigned it. A bold step but one that appears to have completely paid off. Petzl’s updated documentation for the Croll can be found here.

2013 Petzl Basic

The 2013 Basic is the newest piece of kit to hit the shelves from Petzl. Just like the 2013 Croll it has had a complete redesign. I will probably sound a bit like a parrot here repeating lost of stuff from the Croll comparison but I’ll be as brief as possible.

Again the Basic has been on a diet, dropping from 135g to a skinny 90g. If you were to make the switch from the previous jammer versions to the 2013 ones you’d save a total of 85g, that’s the equivalent of a 3rd jammer in your pocket. You could even stop your New Year diet 0.19lbs early or not feel guilty about bringing that extra bag of Haribo underground.

Just like the 2013 Croll, the Basic has shrunk. Perhaps not to the same degree as the Croll but the unit feels noticeably more compact in the hand, not to mention comfortable.


The upper section of the Basic is now fitted with a gentle curve and a matching section of plastic. These changes fit my hand like a glove, feeling comfortable with a left or right handed grip. I may however find it a little harder now they are so easy to hold to coach efficient technique with out over reliance on arm strength.
Another big change is the loss of the double hole at the top. In the past we have been able to build pulley-jammers or mechanical advantage SRT systems by placing a karabiner through the top holes and capturing the rope. This is no longer possible on the 2013 version but have no fear, Petzl have thought of that and given us the solution.
The new lower attachment point is double size, allowing 2 karabiners to be clipped in.

The previous version of the Basic allowed us to clip into the top attachment holes for use in tyroleans, pulley systems and rescue:


The 2013 version allows us the same versatility but with a simpler, single attachment point:


The only use that the Petzl documentation indicates for the top attachment hole is to add weight to help reset a z-rig hauling system. You should probably read Petzl’s documentation if you don’t understand that.

The final big change to the use of the Basic is involving pulley-jammer setups, the kind of hauling and rescue technique that an instructor first learns. The new advised method is arguably simpler to arrange and easier to learn. It does however require an extra krab over the previous method.


I intend to spend some time hauling weights on this arrangement but I really expect no loss in function over previous techniques.

Although it may take users a little while to adjust to the new method of use, I think that the 2013 Basic is a good addition to the Petzl family and combines nicely with the Croll to shrink both the size and weight of the average SRT kit. I think that I could remove my new Basic and 8mm footloop assembly and put it in my pocket between pitches.

One moan (well it can’t be all singing Petzl’s praises), bring back the bright colours! I love my new Basic but I know that one day I’ll drop it in a puddle or sump whilst I’m sorting my harness out and because of its stealth colour I’ll not be able to find it again. Give us a choice of tactical colour for the bandit runs and military users but lets have some red, purple, orange or lime greens for the people who don’t wish to blend in!

Final Thoughts

Interestingly, neither the 2013 Croll or Basic are listed as having a breaking strength or working load limit. The closest we get is the advice that for industrial users Petzl do not recommend the use by anyone over 100kg.
I think this reflects the attitude where the jammers are not placed in situations that require them to hold more than a person’s weight and high load scenarios like traverses and rescue have specialist rigging kit. The issue we may have with this is in a spare rope rescue scenario where we pick off a caver from one rope and accompany them to the floor on another rope attached via a Basic or Ascension jammer. Petzl has an online tool to advise people over 100kg how to use the equipment and that appears to show that correct use of a Croll (i.e. no fall factors!) will be fine with larger loads. For an Ascension it suggests increasing the shock absorbency of the attachment point, i.e. using a dynamic safety link or a cowstail as is widespread in Europe.
I’d still like to see some figures from Petzl for 9mm and 10mm rope to confirm that we can continue to use the Basic in the above way. I don’t expect any loss of strength but it would be comforting to know for sure.

Finally, with all this lovely new lightweight and compact kit coming to our shores, when can I expect a nice redesigned Stop descender?

New Bolts at Pindale Farm

Recently I have been spending a lot of time swinging about on the surface, either through testing knots or coaching SRT skills. For all of this I’ve been using the excellent tower facility up at Pindale Farm near Castleton.
The SRT platform offers scaffolding bar belays and back-ups and the surrounding walls of the old mining buildings are equipped with many 8mm anchor sleeves (Spits) and a few alloy Troll hangers. You can rig just about any permutation of SRT pitch your brain could possibly come up with.
Using the tower over the past few years I’d noticed the deterioration in some of the anchors and as I was such a frequent user I thought some of the replacement anchors should be paid for out of my pocket.

Yesterday (19th March 2013) I managed to procure both equipment and assistance.
Jez Parr CIC (contact) was kind enough to loan me his SDS drill and all the bits for the job.
Nigel Ball CIC (Website) donated half of the anchors and 90% of the expertise in the operation.

We placed 4 new Petzl P38 Longlife anchors on the main wall of the facility; a line of 3 forming a traverse and pitch head which then drops to a rebelay or deviation on the 4th anchor.
We also lubricated and cleaned out all of the 8mm sleeves with a threaded tap to give them a new lease of life.

The tower is now a mix of anchors and can be used with or without hanger plates. Please bare in mind that the tower is equipped by volunteers/individuals and is on private land so booking is essential. Users are reminded to check the anchors they use are safe before commiting their life to them as they would underground and that anchors should never be used alone but as part of a safety chain.

Pindale Farm is an excellent place to stay in the Peak for caving or any other reason. They have camping and bunkhouses on their site as well as the excellent SRT tower.

One of the best and most important aspects of camping is how it helps you build and strengthen relationships. When you go camping with friends or family, you get a chance to talk and visit without distraction, even late into the night. Physical fitness: Time spent camping is physical time. To better better be prepared against animals and snakes you may run in to the way, visit campingfunzone.com for their vast information about camping, insects and animals.

New bolts circled:Pindale Tower

Conclusions on the use of the BotB

So, the footage has circulated, tests have been done and reports and statements have been published. Where are we on BotBs?

I echo the BCA advice that the BotB is safe to use provided that a cowstail is always clipped into both loops. I will continue to use the knot in my range of personal and professional tools. I think that the knowledge of this method of failure has been there since the BotB came into use, I do think that a number of people were shocked as to the extent of the failure when they saw it. This knee-jerk away from the BotB has calmed down as people have looked into the evidence and scenarios of failure.
Hopefully enough information is out there now to allow cavers to make their own choices on knot application.

A concern may crop up for some riggers where they are leading less experienced cavers or those who simply do no know about the single loop issue. The rigger may descend the pitch and those following could inadvertently clip a single loop placing them at risk of this failure. This scenario perhaps would benefit from the use of a knot that won’t fail if a caver clips a single loop – However the advice to clip both loops does not change.

What if you don’t want to use BotBs?

Well, a number of suggestions have been put forward.
The Fig 8 ‘Bunny Ears’ / Double Fig 8 on the Bight is the most common knot but lacks the ease of adjustment and untying that the BotB has.
The Fusion (Karash) Knot is simple enought to tie but is a struggle to dress on stiff rope and has zero history in UK caving prior to a few months ago.
Alpine Butterflys or Caver’s Butterflys can provide a good Y-hang but an overhand knot would need to be introduced to one of the loops to give a central rescue point.
The Double Bowline on the Bight is one extra twist from the BotB. It adjusts, ties, unties and looks like a BotB, meaning it is easier to use and spot mistakes for existing BotB users.

The choice is down to the individual rigger. The evidence is out there for you to see.

Warning – correct use of Bowline on the Bight Knots

BCA’s Training and Equipment & Techniques Committees would like to highlight the importance of ALWAYS clipping a cowstail through BOTH loops of a Bowline on the Bight knot. Although this has been taught for years by BCA instructors, it appears
that many cavers are not aware of the importance.

The problem is that in a fall the knot can slip in such a way that the rope going down the pitch can actually run all the way back through the knot. This means that a caver falling
at a pitch head with their cowstail clipped into only ONE of the two loops could
potentially plummet all the way to the bottom of the pitch. This cannot happen
if they are clipped into BOTH loops.

A useful tip is for the rigger to leave an HMS karabiner clipped between the two loops to make it easier for the rest of the party to clip in and it is always worth remembering that two cowstails are preferable to one.

From here: http://www.british-caving.org.uk/?page=150

The report from drop tests at BPC on the 30th Jan 2013 is here: http://british-caving.org.uk/equipment/Initial%20results%20from%20a%20Preliminary%20Investigation%20into%20Y%20hang%20knots.pdf

UKCaving discussion here: http://ukcaving.com/board/index.php?topic=14602.msg191183;topicseen#new

2nd round of testing on the Bowline-on-the-Bight knot

Thinking that 2 heads were better than one I set out today with a good friend and colleague, Jez Parr. Jez in another CIC holder with many years of experience. He was also my mentor through the CIC scheme and the ideal person to bounce ideas off.

Our first stop was local gear shop and purveyor of lovely shiny things, Hitch N Hike. We purchased 5 metre lengths of all the most commonly used semi-static rope they had, in both 9 & 10mm. The test this time was set up identically to the ones done previously on the 8th Jan. We had a mock Y-hang arrangement that allowed us to position the test ropes at varying heights and angles as well as a solid bar from which to rig a secure dynamic safety back-up for ourselves.
The aim of the first testing done previously was to identify the main contributing factors that caused the failure in the Bowline-on-the-Bight, or BotB. This was achieved and we could generate failures almost 100% of the time. This test is written up in the last blog post.
Today’s testing was all about trying to get a failure in a normal use environment with normal conditions. All the tests we did were on knots that has been tied, dressed and set as we would and have done thousands of times underground. We were not wanting to tie sloppy knots, we wanted to see if it would fail when it was done well.


For every test of every rope in every combination of orientations we tried, so long as the cowstail was attached through both loops of the knot there were no failures. This was as expected and ties in with the best practice advice that has been taught for years with the use of the BotB – ALWAYS CLIP BOTH LOOPS.

For tests carried out where we dropped onto a single loop – the one formed from the traverse line or stopper knot, we could also generate no failures. However this is outside the intended use of the knot so little time was spent investigating that scenario.

When connected to the Bowline-on-the-Bight with a cowstail attached to the single loop formed by the pitch rope we were able to generate failures in knots that were tied and dressed correctly that had been hand tightened or on occasion body weight tightened.

Below are a pair of images showing slip through the knot. Note the blue mark.
BotB test 3

BotB test 4

A second set of test images:


For the previous test film see here:


The Bowline-on-the-Bight can fail when you are clipped into a single loop and the knot is dressed correctly and tightened. The failures we generated included ones where we both agreed that we had tied a perfectly acceptable BotB before testing.
Although we can identify many modes in which we could not get a failure to occur, the fact that one can occur in normal* use is very worrying.

* normal use if you only use one loop to attach your cowstails as is against the best advice – always clip through both loops!

So now what?

Cavers should draw their own conclusions from these tests or indeed conduct their own perhaps.
I believe that it is still appropriate to teach the Bowline-on-the-Bight as one of the standard knots for caving alongside the information about how to use it safely and the consequence of misuse.
I will copy this information to the British Caving Association for review. It is not my place to advise on caving policy for the UK.

I have been offered the chance to use a rope tester to look at potential replacements for the BotB. The test will give us a chance to see how a replacement compares with the existing methods in terms of strength and durability.
The French’s preferred option – the Fusion Knot, which has also been called the Karash Knot, is high on the list of contenders but I feel that a similar knot to the BotB would be more easily absorbed by the caving community. Both myself and Jez think a closer look at the Double-Bowline tied on the Bight may give a very good alternative. We’re calling it a D-BoB, or Double Bowline-on-the-Bight, until we can establish its correct name.

Testing a method of failure with a Bowline-on-the-Bight knot

A recent video clip has come to light on UKCaving Forum from the French Caving School which identifies a method of failure for the Bowline-on-the-Bight knot. The School’s film shows a failure that could lead to serious injury or even death when clipped into only one arm of the Y-hang.
I have not seen or heard of any occasions where this failure has happened in the U.K. and have certainly not seen it with my own eyes until today’s tests. It is rare for such a statement to come in regards to such a well used technique so I had to investigate.
We made use of the excellent training facility at Pindale Farm in the Peak District and the not so excellent weather.

The Bowline-on-the-Bight or ‘BotB’ knot is widely used and taught as a preferred knot for most SRT rigging applications involving Y-hangs and SRT. The knot has certain shock absorbing and self equalising properties that make it a good choice. These traits form one side of a double edged sword, the other side being the knot is easy to undo and therefore easier to loosen in use. It is this property of the Bowline knot family that can lead to slipping failures like the one we are looking into here.
For anyone who does not know the BotB knot, I will not explain it here as there is a wealth of literature and information on them online. Spend 5 mins Googling or pick up a copy of a UK caving manual.

The Failure:
The problem occurs when a caver is clipped into one arm of the Y-hang formed by a BotB. The two arms are formed from different parts of the knot, one coming from the pitch rope up into the knot, twisting round and emerging to form a loop and the other from the traverse line or on occasion a stopper knot.
Being clipped solely into the arm formed from the pitch rope can cause the rope to pull through and effectively untie the knot when loaded by the caver. If on a straight pitch with no other attachment the caver could fall to the floor. Even with a re-belay or end of rope knot present to stop the rope being pulled totally up the slip can still occur. I ruined a length of rope today, wearing through the sheath on a slip of less that 2 metres.

We managed to work through a set of differing conditions and factors to arrive at a scenario where we could generate an almost 100% failure rate. We used the same rope throughout the tests, although the knot was tied in different sections to prevent too much damage to the same area.
The rope was a 5 year old length of 10.0mm semi-static rope widely used by cavers. We also tested a length of smaller diameter rope from another brand with similar results. The rope was stiff but could still form and hold a knot well.
We varied the knot for each test in the following ways:

  • Dressed correctly or not
  • Tightened or not
  • Evenly loaded or not
  • Clipped into left or right arm
  • Clipped into both arms
  • 10 & 9mm rope tested
  • Wet and dry

In the outdoor world we use a accident analogy called the ‘Lemons’. If you imagine a slot machine is your work and the tumblers and their ‘fruits’ are the small events that happening, the lemons are the poor practice, bad judgement or bad events.
As a lemon appears on a tumbler it is usually outweighed by a good fruit, i.e. a bad thing/poor practice is safeguarded by the other good practices along with it and the chance of an accident is low.
When all the lemons come up on a line together we have a series of poor decisions or events that collectively form a chain of events and choices which dramatically increase the chance of having an accident. Hence, it is better to follow the adage of prevention being better than cure. It is this analogy that I think fits perfectly with this method of failure in the BotB.

When the following conditions were met we experienced a near 100% failure rate.

  • Wet rope (very high rate of failure on dry too)
  • Knot not fully tightened
  • Y-hang arms not equally loaded – specifically the one formed by the pitch rope
  • Caver only being clipped to the loop formed by the pitch rope
  • A dynamic fall similar to someone slipping on the lip of a pitch
  • Knot recently tied – i.e. first person down after rigging.

It is worth noting that we did have other failures with different test conditions but on a far smaller percentage of tests. The loose arm being the common factor in all of our testing.

Best Practice:
We teach what is known as best practice. This ideal of coaching changes and we are constantly evolving our advice. This is one of the reasons I went and did these tests today, to ensure that what I did was still the best it could be.
Current best practice advice for SRT, rigging and progression where relevant to this article is as follows:

  • Rope used should be of good condition and supple enough to hold a knot well
  • The rigging should be tight and all knots dressed correctly and tightened down before use
  • Y-hangs should be loaded equally
  • The caver should always have their cowstails clipped into both arms of Y-hangs (you’ll notice we use larger krabs than most for this reason)

We experienced no test where a failure occurred when all of the best practice conditions above were met.
Failures did occur in other tests, the chance was lower unless all of the ‘Lemon’ factors were involved.

Under no circumstances should you use a technique that is unfamiliar to you. Get trained, get experienced, get informed.