When FLUSHMATE is empty of water, it contains air at atmospheric pressure. As water from the supply fills FLUSHMATE, the air becomes trapped and is compressed. As air pressure builds to equal line pressure, water flow stops. The FLUSHMATE is ready to flush.
It's compressed air inside FLUSHMATE that increases potential energy of the entire system. The 1.6 gpf (6.0 Lpf), 1.28 gpf (4.8 Lpf) or 1.0 gpf (3.8 Lpf) of water that flows into FLUSHMATE becomes "turbocharged" by the air, giving the water flushing performance equal to 5-1/2 gallons or more.
When the toilet is flushed, this energy pushes the water into a specially designed toilet bowl. A toilet equipped with FLUSHMATE must be specifically designed to accommodate the effectiveness of FLUSHMATE. FLUSHMATE is NOT a retrofit product.