Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number H19-273 found under Valve Plug by Dresser Industries Inc. The National Stock Number assigned to this part is 4820003655738, and the Federal Supply Class is 4820 Valves Nonpowered. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like H19-273.