Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number MS51990-105P found under Ring Lock Serrated by Tecno Trade S R L. The National Stock Number assigned to this part is 5365004057576, 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 MS51990-105P.