Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number HO3 4X3 4-2.5-29-B-1M-MS found under Meter Flow Rate Indicating by Hoffer Flow Controls Inc. The National Stock Number assigned to this part is 6680014307039, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like HO3 4X3 4-2.5-29-B-1M-MS.