Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number K55-0012 found under Bearing Roller Need by Ward Leonard Electric Company Inc. The National Stock Number assigned to this part is 3110016178472, and the Federal Supply Class is 3110 Bearings Antifriction Unmounted. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like K55-0012.