Mechanical Manifold Gauge Set Number of Valves 2 R-12 R-22 R-502 Number of Hoses 3 72 in 0 to 500 psi 30 in Hg to 350 psi Aluminum With 2 3/4 in Diameter High and Low Side Dry Gauges Piston Style Valves Includes Blind Ports On Manifold For Hoses When Not In Use Hook SAE Approved Hoses Sight Glass