QUALITY MATERIAL - Tungsten carbide tipped cutter and anti-rust electroplated steel drill bit body, built for faster penetrating, prolonged life and heavy-duty use. PROFESSIONAL lDESIGN - Spear-shaped design will effectively reduce breakout. MULTIPLE PURPOSE - These masonry drill bits can easily penetrate tile, terracotta, concrete, cement, ceramic brick, glass, plastic, cinderblock, wood and many more. Please try to keep the drill vertical and use water or coolant for lubrication when drilling. Don't use these bits to drill hard tile. 10PC BITS - The set includes 10pc of 3/16" dia. tile and glass drill bits, well packed in a plastic case for easy storage and transportation. HEX SHANK - Hex shank shank allows for stable holing and quick release in power drill. 1/4" hex shank design for quick release. Multi-functional Masonry Bits Set