26 Solutions for Cleaning & Hygiene Control Unit Plus for OPL Advantage Control Unit Plus provides additional operator benefits, featuring <  19 Formulas <  Auto formula select Solenoid valve <  Plastic cabinet and low voltage power supply <  Check valve between solenoid valve and chemical injection area OPL Advantage Accessories Flush kit for OPL Advantage Flush manifold < Conveniently mounts directly beneath the cabinet < Injection fittings equipped with built-in check valves. Position is adjustable for ease of tubing installation Level control and suction devices for OPL Advantage < Optional, externally mounted, empty product alert system available < Fast and safe connections for foot filter and tubing fittings