Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number HM2840 found under Headset Microphone by D C M Industries Inc. The National Stock Number assigned to this part is 5965001063195, 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 HM2840.