Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 172DN1 found under Ring Retaining by Otis Elevator Co. The National Stock Number assigned to this part is 5325004468698, 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 172DN1.