Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number MM 6B 135F NP139 found under Switch Pressure by Nason Company The Inc. The National Stock Number assigned to this part is 5930016565042, and the Federal Supply Class is 5930 Switches. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like MM 6B 135F NP139.