Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number B1803-55-11 found under Standoff Threaded S by Lta D Cemco Inc. The National Stock Number assigned to this part is 5340005296127, and the Federal Supply Class is 5340 Hardware Commercial. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like B1803-55-11.