The new generation of adjustable proportioning valves combines the latest refinements to deliver precise pressure metering and strength from a compact forged billet design. Pressure adjustments range from 100-1000 PSI and provide for a maximum decrease of 57% in line pressure, the most of any available valve. Adjuster knob with fine thread tuning provides precise pressure adjustment. This adjustment lets you fine tune the front to rear braking balance by proportionally decreasing the rear brake line pressure. Valves weigh only 5.2 ounces and have two .25 side mounting holes spaced 1.00 apart. Standard in and out ports are 1/8-27 NPT.