Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number B5020 1 2 found under Slide Directional Control Linear Valve by Brand Hydraulics. The National Stock Number assigned to this part is 4820012220193, 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 B5020 1 2.