Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 503-0142-01 found under Power Supply by Welch Allyn Inc. The National Stock Number assigned to this part is 6120016000888, and the Federal Supply Class is 6120 Transformers Distribution And Power Station. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 503-0142-01.