Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number A51B52591-411 found under Nut Plain Rectangul by Howe Machine And Tool Corp. The National Stock Number assigned to this part is 5310010920996, 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 A51B52591-411.