Mac Valve 4 Port Electronic Boost Control Solenoid - BARE UNIT / NO FITTINGS - MAC4PORTThis part number is the BARE UNIT. Fittings and filter are NOT included! The MAC 46 Series is a high flow direct solenoid operated 4 way poppet valve. It features a short stroke solenoid with oval armature, a balanced poppet and conical seats. These features translate into high shifting forces, fast consistent response times, high flow in a small package and long life. They are pressure tested to 100 PSI.