I’ve been asked recently what the different gradings mean for boots and crampons in preparation for Alpine adventures for the summer (covid allowing travel of course)– and also to lands afar, so here’s a simple guide which should help.
What are Crampons used for?
Crampons have been described by Cox et al. as a traction device that is attached to footwear to improve mobility on snow and ice. They are toothed devices that fit onto the soles of specially designed boots to give the wearer secure traction on hard packed snow. Crampons are utilised extensively by mountaineers and walkers in traversing glaciers, snowfields, icefields, ascending snow slopes and by alpinists/climbers for scaling ice covered rock as well as climbing ice structures. The original crampon was designed by Oscar Eckenstein in 1908 with the design then being made commercially available by the Italian Henry Grivel. His design has since formed the foundation of what all modern crampons are based around.
What do Crampon Ratings Mean?
C grades are intended to help match the user’s boot and intended use of a crampon. The general rule is that the boot must be stiffer than the crampon, to ensure secure attachment and thus preventing it from falling off. The categories are characterised by the stiffness, binding and point design of the crampon. They are graded as follows:
This style of crampon is referred to as ‘Strap-on’ features a pair of nylon webbing straps that pulls malleable cradles around the heel and toe. This binding system allows for a degree of flex and is suitable for B1, B2 and B3 boots. These do take longer to attach to boots than other styles, however they are lighter than their counterparts. A traditional C1 crampon usually has 8-10 less aggressive points and are described as flexible. These are recommended for winter walking and glacier traverses.
Usually referred to as ‘Hybrids’ but are sometimes called ‘Mixed’ or ‘Semi step’. These feature the same malleable cradle and toe strap as a C1, however, they also host a heel lever. The binding system of C2 crampons is compatible with B2 and B3 boots as they require a stiff sole and heel groove to lock onto. A traditional C2 crampon usually has 10-12 points that include secondary spikes, that are semi sharp. These are ideal for winter climbing and alpinism.
This style combine a metal toe bail with a plastic heel lever and as a result they are referred to as ‘Step in’. The Step in system requires very stiff boots with a both a crampon heel and toe groove, because of this they are only compatible with B3 mountaineering boots. C3 crampons tend to have 12-14 points that offer the best performance on steep icy slopes and technical mixed routes. Additionally aggressive front points offer the best penetration on hard ice and on some models the front tips are replaceable. These are ideal for the hardest Scottish winter climbs and high altitude ascents.
The spiked teeth that bite into snow and ice are referred to as crampon points, they are situated at the contact areas beneath the forefoot and heel. While the amount of points differ between crampon grade and affects where where a crampon will find traction they nearly all have four points beneath the toe and heel.
The Flex Bar is a piece of metal that joins the plates of a crampon. This component allows for crampons to be sized to the wearer’s boot size and the way it attaches to the plates dictates the flex of the binding.
Anti-Balling Plates, alternatively referred to as the ‘Antibot’ are designed to mitigate the collection of snow compacting at the base of the crampon, this would result in slippage of the user, and the compromisation of either plate. They are made of a rubber compound in a dome shape and clip into the base of each plate. They are included as standard with crampons and are easily replaced should they become damaged or lost.