Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 074 1B138 found under Nut Bearing by Gap Instrument Corp. The National Stock Number assigned to this part is 5310003504316, 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 074 1B138.