Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number K57421SUB13PT5 found under Grommet Nonmetallic by L3 Communications Corp. The National Stock Number assigned to this part is 5325002981391, 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 K57421SUB13PT5.