Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 539-040-019-603 found under Boom Microphone by Roanwell Corporation. The National Stock Number assigned to this part is 5965010497236, and the Federal Supply Class is 5965 Headsets Handsets Microphones And Speakers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 539-040-019-603.