With the 210B SRA slab rider, you can stitch or drill horizontally, vertically or at an angle with exceptional accuracy and no disturbance to the subgrade. The unit can drill 5/8- to 2-1/2-inch-diameter holes to 18-inch depths, and it has an auto-alignment feature that tracks the hole placement level for fast and easy repositioning. A roller bearing feed system provides friction-free drilling for longer wear life, less maintenance and minimized downtime.