Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number AT50 50S-IV74 found under Tip Optical Adapter by Olympus Scientific Solutions. The National Stock Number assigned to this part is 6650015402150, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like AT50 50S-IV74.