Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number W4300-045 found under Washer Special by Hansome Energy Systems Inc. The National Stock Number assigned to this part is 5310010463014, 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 W4300-045.