Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number NB402-4-13 found under Bolt Bonnet by Pima Valveinc. The National Stock Number assigned to this part is 5306015764286, and the Federal Supply Class is 5306 Bolts. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like NB402-4-13.