ROETIN Carbide Runners have all the features you need for various levels of performance, from the casual trail rider to the extreme. The X-10 ONE Carbide (Trail/Touring) uses 4" of 90 deg. carbide on a 7/16" bar with 1" wear pads front and rear combined with an extra long master weld fiber. The X-10 TWO Carbide (Agressive Trail) uses 6" of 90 deg. carbide on a 7/16" bar with 1" wear pads and a full-length master weld fiber. The X-PR 1 Carbide (High Performance/Trail) uses 6-1/2" of 60 deg. carbide on a 1/2" bar with FOUR wear pads for longer life. The X-PRT Carbide (Extreme/Agressive) is designed for the high performance snowmobiler, and boasts 9" of 60 deg. carbide on a 1/2" bar, with FOUR wear pads to extend life. The ROETIN carbides also feature 1" studs to accept ski skins. (Sold in pairs)