Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number MT-019B found under Nut Self Locking Ex by Jet Equipment And Tools Inc. The National Stock Number assigned to this part is 5310015667799, and the Federal Supply Class is 5310 Nuts And Washers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like MT-019B.