Heavy-Duty Double Acting Hydraulic Valve 2 Spool, 21 GPM & Spring Return Feature. Heavy-Duty Double Acting Hydraulic Valve - 2 Spool. Unlock the power of performance with our Heavy-Duty Double Acting Hydraulic Valve, designed for precision and reliability in hydraulic systems. With its key features and user-friendly design, this valve is the perfect solution for anyone looking to elevate their machinery operation. Hydraulic 2 Spools Valve with G1/2 type inlet/outlet ports. Maximum pressure of 3600 PSI, with a flow rate of up to 21 GPM. Ideal for small tractors, tractor loaders, ...