Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 1913-501-3 found under Heating Element Electrical Nonim by Treadwell Corporation. The National Stock Number assigned to this part is 4520002957780, 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 1913-501-3.