For Concrete Floor Grinding For greater safety, the concrete grinder is equipped with safety switch to prevent accidental starting. Spindle lock for quicker and easier discs changing. Speed control switch design, Six-speed regulation meets different needs This polisher boasts of a Quick Change Wheel Release that allows tool free wheel removal and a replaceable brush skirting to maintain a high level of dust collection. Sliding concrete grinder dust cover to easily reach to the flush wall edge grinding. In-built adapter to connect to vacuum cleaners, connects to P.I.T. vacuum.