Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number A0L4166-204 found under Screw Cap Socket Head by All Manufacturers Inc. The National Stock Number assigned to this part is 5305003166848, 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 A0L4166-204.