The Model-D is designed for the trails with its longer rear end, higher bottom bracket and mellower headtube. We didn’t attach the trail name so we could disguise a light weight frame. We designed the frame around specific users. This is for trails where a Second Wave would be for street. Simple! Proven 41-Thermal process Lifetime warranty colors: Olive Green and Silver top tube lengths: 20.75”, 21 and 21.25” head tube angle: 74° seat tube angle: 71° bottom bracket height: 11.8” chain stay length: 143 weight: 4.65 lbs.