Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number H3991X3-4X6 3-4 found under Caster Swivel by Stewartwarner Bassick Corp. The National Stock Number assigned to this part is 5340006709799, and the Federal Supply Class is 5340 Hardware Commercial. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like H3991X3-4X6 3-4.