Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4431020 00A found under Assembly Microphone by B E Aerospace Inc. The National Stock Number assigned to this part is 1660016201634, and the Federal Supply Class is 1660 Aircraft Air Conditioning Heating And Pressurizing Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 4431020 00A.