Accurately detect exit points before drilling and coring with the Zircon® ExitPoint® XL300 through-hole drill guide. The XL300 is the easiest and fastest way to locate a precise spot, without measuring, before you start your project. Scans through most types of non-magnetic building materials, such as wood, drywall, gypsum panels, bricks, and poured concrete up, to 11.81 in. (30 cm) thick.