... quality, reasonable price 3. No noise, high efficiency NOVO's Sprocket chain:1. Material: Aluminium, Cast Iron, Steel.2. Surface Treatment: Black ... , Sichuan province, China(Mainland).What we manufacture and where we sell:timing belt pulleys,locking assemblies,torque limiter, gear,couplings,shaft ... good qualityCertification:We've been ISO9001:2000 certified since 2003. Sprocket Chain/ Sprocket gear