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Piston flushometers are precision metering valves designed to deliver a preset volume of water to a sanitary fixture (i.e., toilets and urinals). These are manual flushometers with the following features: GEM-2 § Piston Operated with ‘O’ Ring Protected § Filtered Metering By-Pass Orifice § ADA Compliant Handle § Bak-Chek Control Stop w/ Threaded Vandal § Resistant Cap § Sweat Kit with Cast Set Screw Wall Flange § High Copper-Low Zinc Semi-red Brass Castings § Non-Hold Open & No External Volume § Adjustment to Ensure Water Conservation § Fixed Volume Accuracy ROYAL - Permex Synthetic Rubber Diaphragm with Dual Filtered By-Pass - ADA Compliant Handle with Triple Seal Packing - Bak-Chek Control Stop with Free Spinning Vandal - Resistant Cap - High Back Pressure Vacuum Breaker with One Piece - Bottom Hex Coupling - Sweat Kit with Cast Set Screw Wall Flange - High Copper-Low Zinc Semi-red Brass Castings - Non-Hold Open & No External Volume Adjustment to Ensure Water Conservation - Fixed Volume Accuracy with CID technology SLOAN - Permex Synthetic Rubber Diaphragm with - Linear Filtered By-Pass Orifice - ADA Compliant Handle - Bak-Chek Control Stop with Vandal - Resistant Stop Cap - High Copper-Low Zinc Semi-red Brass Castings - Non-Hold Open & No External Volume - Adjustment to Ensure Water Conservation - Fixed Volume Accuracy with CID Technology REGAL - Natural Rubber Segment Diaphragm - With Fixed Metering By-Pass Orifice - ADA Compliant Handle - Bak-Chek Control Stop with Threaded Vandal - Resistant Cap - High Copper-Low Zinc Semi-red Brass Castings - Non-Hold Open & No External Volume - Adjustment to Ensure Water Conservation - Fixed Volume Accuracy - With Para-Flo Technology