The QEP Xtreme 1-3/8" (35 mm) Diamond Hole Saw with Water Delivery System to drill holes for installation of bathroom fixtures in glass, stone, marble, granite and porcelain tile, as well as concrete (depending on thickness). In addition to the 1-3/8" hole saw, the kit contains water reservoir, drill guide, and 6 single-use adhesive pads for mounting. This hole saw must be used with the water reservoir to keep it from overheating, and must be used with a cordless drill.