Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number GT303P4B2 found under Valve Diaphragm Stop by George W Dahl Inc. The National Stock Number assigned to this part is 4820004762962, 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 GT303P4B2.