WIDE COMPATIBLE: Suitable for 4/5/6/7/8/10/12mm drill bits. Drilling holes for glass, tile bottles, block jars, fiberglass porcelain, ceramic, mable slate, light granite and more VACUUM BASE: Attaches to most tiled surfaces using the lever vacuum base. The suction cup base has good strength to hold the center template firmly and securely on a smooth surface. EASY TO USE: Sturdy handle, easy to move and use. The drill base with strong grip ensures that the drill guide does not move, making your operation smoother. It makes tile holes more precise DURABLE PLASTIC: Advanced thickening engineering plastic is wear-resistant and durable. Made with high quality sealed bearings for high strength and durability. Easy to store and reuse ACCURATE POSITIONING: Ideal for hard to reach places, such as drilling horizontally into a tiled wall or drilling vertically into floors is much easier with this guide. Note: The data is all measured manually, please allow 1-3 cm error due to light and display