Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 66551-3 found under Valve Gage Assembly by Air Cruisers Company Llc. The National Stock Number assigned to this part is 4240015534219, and the Federal Supply Class is 4240 Safety And Rescue Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 66551-3.