Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 427531-1 found under Screw Cap Socket He by The Entwistle Company. The National Stock Number assigned to this part is 5305013528462, and the Federal Supply Class is 5305 Screws. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 427531-1.