WEST SYSTEM's Positive Displacement Metering Pump dispenses five parts resin and one part hardener by volume. It consists of two separate parallel pump systems, one for the resin and one for the hardener. The two systems are operated simutaneously by a single lever. The pump delivers 2.3 fl. oz. of resin and hardener per full stroke of the dispensing lever. The reservoirs hold two gallons of resin and one gallon of hardener. For use with 205 or 206 (5:1 ratio) hardeners.