Hollow Hydraulic Ram, Single Acting, Hollow Plunger, Steel, Nominal Capacity 12 ton, Max. Push Capacity 12ton, Stroke Length 1/4 in, Nominal Stroke Length 5/16 in, Effective Push Area 2.76 sq in, Max. Pressure 10,000 psi, Oil Capacity Push 0.86 cu in, Retracted Height 2.19 in, Extended Height 2.5 in, Outside Dia. 2.75 in, Plunger Dia. 1.38 in, Plunger Thread Size 3/4 In. 16, Collar Thread Size 2-3/4 In. 16, Base Bolt Circle Dia. 2 in, Base Mounting Thread Size 5/16-18, Center Hole Dia.