Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number MX540-2PC37 found under Heating Element Electrical Immer by Pottstown Water Heater Co Inc. The National Stock Number assigned to this part is 4540009104049, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like MX540-2PC37.