Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 306A found under Piston Valve by Ruthman Pump And Engineering Inc. The National Stock Number assigned to this part is 4820003436043, 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 306A.