Large capacity for powering variety of cylinders and tools. Featuresinternal pressure relief valve for overload protection. External load release valve for single-acting cylinder operation. No. P-39. Single-speed. Maximum handle effort of 111 lbs. 40 cu. in. oil capacity. Pressure Rating PSI 1st Stage: - Pressure Rating PSI 2nd Stage: 10,000 Oil Disp. Cu. In.* 1st Stage: - Oil Disp. Cu. In.* 2nd Stage: .16 Note: Oil disp. Cu. In. measured per stroke.