AST AST800 4020 plain bearings

Plain Bearings 1.3750 in inside diameter: offers a AST AST800 4020 plain bearings Dacheng mechanical equipment manufacturing Co., Ltd selection of Genuine 717905199240 manufacturer upc number: Plain Bearings at Wholesale Prices. We are a AST AST800 4020 plain bearings Certified -250 to 550 ºF operating temperature range: Parts Retailer

What is AST800 4020 bearing cross reference？