Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4J-865 found under Spindle Timing Belt by Bridgeport Machines. The National Stock Number assigned to this part is 3417012064477, and the Federal Supply Class is 3417 Milling Machines. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 4J-865.