Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 55831 found under Cap Assy Sight Gaug by Honeywell Aerospace. The National Stock Number assigned to this part is 1660004853330, and the Federal Supply Class is 1660 Aircraft Air Conditioning Heating And Pressurizing Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 55831.