Do you have the feeling of sliding on icy pavements? Are your carbides round quickly and have no teeth left? Here is your solution, the EVERLASTER carbide BLADE-Z carbides which will always remain sharp and until there are no more carbides inside. These are the only OEM replacement self-sharpening healds on the market. Patented in Canada and the United States, these OEM replacement rails will give you maximum durability, optimal grip and longevity. The EVERLASTER carbide BLADE-Z heddles have been designed to be always SHARP, to keep a constant cut and to self-sharpen by themselves.