Description:Part # 9D-8890 provides an air over hydraulic brake cylinder group that provides air boosted hydraulic oil pressure for actuating hydraulic brakes.Attributes:• Conversion Ratio: 11.8:1• Minimum Hydraulic Displacement: 290 cm3• Fluid Compatibility: Mineral Oil; SAE 10W CD/TO-2• Air Cylinder Diameter 152.4 mm (6.0 in) X 187.32 mm (7.37 in) Stroke• Hydraulic Cylinder Diameter 44.45 mm (1.75 in) X 187.32 mm (7.37 in) Stroke• Air Supply Port Thread Size: 1/2-14 NPTF• Outlet Port Thread Size: SAE -6 STOR, 9/16-18• Reservoir Inlet & Breather Port Thread Size: 3/8-18 NPTFApplication:Consult your owner's manual or contact your local Cat Dealer for more information.