This Flat Idler Pulley works both as an OEM replacement and as a general purpose pulley for power transmission such as compressors, industrial fans, lawn mowers, snowblowers, and electric motors. It comes with a bore adapter to bush down from 17mm to 1/2'' inside diameter. 31561431 features a heavy duty sealed radial single-row bearing.This part is Zinc-coated for long-term rust prevention. Additional Features: Made of Steel Flanges angled outward to help increase belt life Direct OEM Replacement for: Industrial Kinetics: 730001