Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number PR10-M4 found under Retainer Turnlock Fastener Eject by Penn Engineering And Manufacturing. The National Stock Number assigned to this part is 5325013672787, 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 PR10-M4.