Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 55N0228 found under Block Hp Manifold by Tool Serv. The National Stock Number assigned to this part is 2990014566654, and the Federal Supply Class is 2990 Miscellaneous Engine Accessories Nonaircraft. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 55N0228.