Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 16Y4022-4 found under Insert Diffuser by Coating Specialties Inc. The National Stock Number assigned to this part is 1660012849936, and the Federal Supply Class is 1660 Aircraft Air Conditioning Heating And Pressurizing Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 16Y4022-4.