... MAK5396-KN28601,5389-KN28600 Market: USA, Canada, South America Mack FF-2 Full Function Valve :Parts No: MAK5396-KN28601/MID KN28601Specification ... : Supply port, (1), 3/8'' P.T, Control Port: (1), 1/4 inch P.T. Reservoir Port: (1), 1/2 inch ... P.T Service Brake Ports: (4), 3/8 inch P.T. 3 psig Cracking Pressure. Width ...