Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number P18C3999 found under Bushing Sleeve by Hamilton Sundstrand Corporation. The National Stock Number assigned to this part is 3120003093028, 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 P18C3999.