Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4L4401 found under Washer Assy Thrust by Caterpillar Inc. The National Stock Number assigned to this part is 3120002859035, and the Federal Supply Class is 3120 Bearings Plain Unmounted. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 4L4401.