... quality and competitive price material: titanium Titanium bicycle drive system with high quality and competitive priceTitanium products includes bolts, ... specifications: 1Common Ground a, Bolt sizes:M4-M22*length b, Nut sizes:M4-M22 c, Standard:GB,ISO,DIN ... 2Difference: a, Titanium for the chemical aspects,PCBequipment,electrodes. b, Titanium alloy used in Bicycle,Motorcycles,Electric Vehicles,Medical, ...