Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number X-83121-014-0 found under Speed Sensor Diesel Engine by Mack Boring And Parts Co. The National Stock Number assigned to this part is 2815015529950, and the Federal Supply Class is 2815 Diesel Engines And Components. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like X-83121-014-0.