You asked for smaller, more portable descalers and we listened. Introducing the the GDS-C92. Constructed of heavy duty polyethylene and acid proof components, these units are designed for years of use in industrial applications. The secret to their success at removing scale lies in the innovative Flow Reversal Valve. During the descaling process, lime scale dissolves and creates foam and gas, which act as a barrier to further scale reduction. Using the Flow Reversal Valve allows for the foam and gas to discharge into the tank, eliminating the barrier effect and considerably speeding up the descaling process. Each unit is self priming and safely contains chemicals within its integral tank, allowing for maximum user friendliness. The GDS-C90 will take care of larger boilers and chillers, heat exchangers and more. 21 gallon per minute (GPM) flow rate.