Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 5540-3316 found under Knob by Iet Labs Inc. The National Stock Number assigned to this part is 5355009287466, and the Federal Supply Class is 5355 Knobs And Pointers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 5540-3316.