Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 91S2-31WO found under Stud Assembly Turnlock Fastener by Alcoa Global Fasteners Inc. The National Stock Number assigned to this part is 5325013511406, and the Federal Supply Class is 5325 Fastening Devices. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 91S2-31WO.