Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number D61-121-8634 found under End Cap Cylinder by Hurst Industries Inc. The National Stock Number assigned to this part is 4240011036884, and the Federal Supply Class is 4240 Safety And Rescue Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like D61-121-8634.