Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number L691 55 ITEM 27 found under Spacer Ring by Ulstein Usa Inc. The National Stock Number assigned to this part is 5365013141888, and the Federal Supply Class is 5365 Bushings Rings Shims And Spacers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like L691 55 ITEM 27.