... quality and competitive price material: titanium Titanium bicycle drive system with high quality ... shaft liners, flange, gear wheel, sprocket wheel. Titanium and Titanium alloy specifications: 1Common Ground a, Bolt sizes: ... M4-M22*length b, Nut sizes:M4-M22 c ... , Standard:GB,ISO,DIN,BS,JIS,ANSI/ASME,BA d, GRADE:Gr2,Gr5 2Difference: a, Titanium ...