Petzl Charlet Irvis Spirlock

This is a very lightweight crampon at just 780g per pair, making it ideal for when you’re not sure if you’ll encounter snow or are just crossing a plateau. There are 10 points, and two of these are turned through 90 degrees to provide extra traction on slopes. There is some 3D stamping in the crampon too to add a little extra strength. The crampon comes pre-fitted with anti-balling plates to prevent snow from sticking to the base. The binding system is very lightweight, thanks to a simple wire frame around the toe and heel that combine with straps to hold the crampon in place. Most noticeable of all is how compact these crampons are when packed away, making them ideal for stowing in a rucksack. The instructions are particularly clear and helpful, and make the use of these easy to understand.  But you only get 10 short points, while others have 12 long points, so these are not the grippiest of crampons. Some other anti-balling plates are arguably better at shifted the snow. The sidelock binding requires a boot with a lip at the toe for the front wire which means it won’t fit as many boots as some other crampons will. Annoyingly, a screwdriver is needed to fit new anti-balling plates. 

Vital stats

Classification C1
Materials NiCroMo steel
Sizes 27-42 (medium); 35-46 (large)
Weight 780g including anti-balling plates
Made in USA

Verdict A lightweight crampon that is ideal for certain boots, particularly for ski touring, glacier travel or when ice is only going to be crossed for a shorter level section of the route.