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unlevel edge
40mm and 20mm

The perfect blend of science and art. The unlevel edge will help get you stronger AND reduce your risk of injury at the same time.


 Created by a climbing specialist physiotherapist from 1000's of data sets and research and hand crafted for comfort in sustainable hardwood by Paul from Crusher holds, making wooden holds for climbers since 2008.​ 

why choose these unlevel edges?

​There are now a few unlevel edges on the market. None of us can genuinely lay claim to be 'the first' or 'the best'. I first saw a commercial unlevel edge about 15 years ago. In fact it was made by Paul and they're still in use today.







We've all researched and tested and come up with our own version of a similar idea. 

I have added this short section in response to a bit of a social media storm about new products coming on the market.


I believe choice is good for customers and none of us should claim to be better than others. We all offer different products based around a similar concept. So I shall set out why I feel you should purchase mine and not get involved in negative comparisons.

I chose a non-organic shape as my testing showed the organic curve or 'bump' encouraged the outer fingers to pull inwards, or fall outwards, down the slope. This will affect their loading ability and introduces rotational forces we know are irritating to fingers. It also showed less force production at 40mm in my testing.

I put channels on the 40mm as this provides the greatest base of support from which to produce force, to get stronger fingers, and the greatest stability for rehab. This is basic S&C principles. You don't get stronger by training on small edges. You can't produce as much force, so the muscles get less stimulus, but you do get greater irritation due to the reduced support. 

This channel design carries through to the 20mm where the edge profile encourages correct orientation of the force without being able to 'nestle' in the 90 degree corners some designs have. Ideal for recruiting and coordinating at the crag. 

My product is made from UK sourced sustainable hardwood and is hand made 10 miles from my office. No air miles here and no plastic (apart from the cord). I also use the most sustainable packaging I can. See here for further info. 

  • All four fingers are loaded to their maximal possible output - level edges overload middle two and underload the outer fingers

  • The hand is forced to maintain contact via the flexor muscles and tendons - not hanging off the friction of the pulley system, skin or compression of joints

  • Joint angles are maintained to avoid compression and the end joint is supported to avoid chronic injury on the 40mm version

  • The deeper edge means you can apply more force and stimulate both flexor tendons - more force sends a stronger signal to the body to adapt

  • The channels the fingers sit in avoid rotational forces being applied to the fingers, but do not allow nestling in a corner. Rotational forces can be particularly provocative for finger injury. Level edges and organic bump edges still allow rotation and stacking of the fingers together

  • The internal hand muscles are loaded much more which is important for the more open handed holds we AND for complex holds where fingers have to work more independently. As with other isometric finger training this strength does carry through to other angles. 

  • Use it to safely get stronger fingers and then coordinate that strength on smaller edges - cycle your training like we do with energy systems


now available in 20mm

People kept asking, so now we have made a 20mm version for benchmarking, training and recruiting at the crag

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Each purchase entitles you to:

  • £10 discount on a physical copy, of my best-selling book 'The Self-Rehabbed Climber'.

  • £15 discount on a face to face, or remote, assessment.

Codes will be sent on purchase.

how to use it

It is pretty simple, but I want people to get the full benefit out of it, so here's what to do. I'd suggest using it to lift from the floor with a Tindeq unit, rather than weights. The Tindeq is much easier to set up and if anything happens you don't drop a weight on your foot.


But it can also just be used to loop around your foot for warming up, or to sling overhead should you wish. 

You should expect to pull about 25% more with the 40mm edge.

You can mono, 2 finger, front 3, back 3 just using the slots. No need for extra pockets.

You can change the sling to single, rather than double, to change the angle for drags, or going to a smaller edge.

 We don't need to be obsessed with measuring everything all the time. Feel is vital. Feel free to benchmark at appropriate intervals on your usual edge so you know you're progressing, or purchase the 20mm version. 


what does it do?

this is what we aim to avoid

Repetitive, loading of the fingers in the same, compressive positions. 

Whilst small edge training does require input during training (so we can tolerate it), it does not make us stronger. It makes us better on small edges.

If you want to maximally recruit the forearm and finger flexors and extensors (to stabilise) then you need a stable base that enables enough repetition without increasing injury risk.

Get strong and then apply it to your climbing. Training doesn't have to look exactly like the sport. If you train like the sport and perform in the sport you are reducing the variety of loading on your fingers and increasing your injury risk.

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the future

Multi block - large un-level edge, 15 mm edges and unlevel pinch block combined 
Bespoke - 3D printed for those who need an individual fit
Wall mounted - for traditional hangs
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