This machine is used to cut the expansion joint on concrete floor. Meanwhile, it can cut and groove all standard manufactures of concrete, marble and granite. It is a necessary machine in the construction of road. Super-rigid box frame ensures straight cuts while resisting warping and vibration-prolongs saw life; extends blade life. adjustment handle with comfortable grip handles, easy crank for raising/lowing cutting depth. Hinged front lift-up blade guard is designed to provide easy blade replacement; easy-remove, rustless poly water tank provides an optimum flow and volume of water to the blade. It uses sheet diamond, which has the virtues of quick cutting speed, and even cut. Meanwhile, sheet diamond could cut the steal beams in concrete. It has simply, safety construction, easy and flexible operations.