Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 550B-42 found under Motor Alternating Current by Fischer George Foundry Systems Inc. The National Stock Number assigned to this part is 6105013043210, and the Federal Supply Class is 6105 Motors Electrical. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 550B-42.