High duty manganese steel, with vacuum heat treatment and tempering process, featured with great hardness and toughness, which increase traction when walking and climbing in snow to reduce risk of falling down. Features: Adjustable length fit for shoes: US 6-13.5 / CN 36-46. High duty manganese steel spikes, strong, tough and corrosion resistant. 12 spikes,1.5in long,can dig into varieties terrain, firm and safe. TPU straps is highly flexible and won't snap. Nylon binding fits for most shoes and boots. Nice ice gripper for snow climbing, ski mountaineering, glacier hiking and etc. Provided zipper bag,easy to store and carry. Specifications: Material: Manganese steel + TPU Fit for shoes: CN 36-46 / US 6-13.5 Spike length: 4 cm / 1.5 in Package weight: 1162 g / 2.6 lb Packing List: 1* Pair of Ice Gripper 1* Storage Pouch