Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number C4551B00 found under Parts Kit Friction Clutch by Formsprag Company. The National Stock Number assigned to this part is 3010013170721, and the Federal Supply Class is 3010 Torque Converters And Speed Changers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like C4551B00.