Boot/Crampon Compatibilty

Over the years there have been many problems and accidents caused by people fitting unsuitable crampons to boots. To resolve this problem Mountain Guide Brian Hall working for Scarpa and Grivel came up with simple scheme to assist walkers and climbers in selecting suitable crampons for their boots.

Like all simple schemes it is flawed in that it is over simplified and we know of more than one instance of people completely flouting these "rules" to their advantage and without mishap - indeed, in mountaineering, there are no "rules", but as a general guide it is useful.

Boots are now rated by many manufacturers for stiffness and the type of use they are designed for.

Rating	Use
B0	Not really suitable for crampons
B1	Flexible boots that are suitable for trekking and hill walking only. C1 crampons only
B2	Semi-rigid boots designed for mountaineering and easier grade snow and mixed climbing, but not for steep ice and harder mixed climbs. C1 or C2 crampons
B3	Fully rigid boots for mountaineering, ice and mixed climbing at all grades - but not always the most comfortable boots to walk in (though things are improving). C1, C2 or C3 crampons

NB : Be aware that the larger a boot, the more flexible it will be, so that a size 47 nominally B2 boot may well be more B1 like. In other words, if you have big feet, you may need even stiffer boots!

Crampons should be no stiffer than your boots or they may fall off and/or give you ankle problems and you may get metal fatigue in the crampons causing them to break.

Rating	Use
C1	Flexible (eg Kahtoola, Grivel G10)
C2	Semi-rigid (eg Grivel Airtech, G12, G14)
C3	Rigid (eg Grivel Rambo, DMM Terminator)

Thus:

Boot Rating	Suitable Crampon Type
B1	C1
B2	C1 – C2
B3	C1 – C2 - C3

Crampon Rating	Suitable Boot Type
C1	B1 – B2 - B3
C2	B2 - B3
C3	B3

Crampon Binding System

In addition the binding system should be suitable for the boot.

There are currently three main types of binding systems, plus one other now discontinued. Be aware that some boots have step in heel welts to make them look "techy" even if they're not. If in doubt a modern type Strap On crampon (eg New Classic binding) is best.

System	Use
Strap On	This includes plastic "basket" type systems. Will fit all boots. Known by Black Diamond as “Strap”, Grivel as “New Classic” and Petzl as "Flexlock and Spirlock”
Semi Step In	This will only fit boots with a proper heel welt designed for semi step in crampons. Known by Black Diamond as “Clip”, Grivel as “Newmatic” and Petzl as “Leverlock”.
Full Step In	This will only fit boots with a proper heel and toe welt designed for full step in crampons. Known by Black Diamond as “Pro”, Grivel as “Crampomatic” and Petzl as “Leverlock Fil”.
GSB	Grivel-Scarpa Binding. Will only fit boots designed specifically for GSB Bindings. This binding has now been discontinued as have the boots made to accept it. It is possible to convert these crampons to Semi or Full Step In types by using various replacement Grivel Bails and possibly Straps.