Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number HS3-A-BK found under Light Head General Purpose by Surefire Llc. The National Stock Number assigned to this part is 6230016220311, and the Federal Supply Class is 6230 Electric Portable And Hand Lighting Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like HS3-A-BK.