For use with standard 12 tooth splined steering columns. 2500 PSI max. pressure. Open center. Four 3/8 -16 mounting holes on 3 1/4’’ B.C. Valves are available in two different load circuit options: Non-Load Reaction: Steering cylinder ports are blocked in neutral, locking the axle position when the operator releases the steering wheel. Load Reaction: Steering cylinder ports are tied together in neutral, allowing the axle forces to return the steering wheel to its original position when the wheel is released (similar to steering in an automobile).