Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4201-1-2 found under Ring Connecting Round by Acco Industries Inc. The National Stock Number assigned to this part is 5365008033392, 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 4201-1-2.