Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number B0437-023 found under Washer Spring Tension by Tap Tool Inc. The National Stock Number assigned to this part is 5310010803799, and the Federal Supply Class is 5310 Nuts And Washers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like B0437-023.