Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number HF550 found under Kit Attachment by Assembly And Test Worldwide Inc. The National Stock Number assigned to this part is 2090011625052, and the Federal Supply Class is 2090 Miscellaneous Ship And Marine Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like HF550.