IRWIN 4935109 DRILL BIT 5/16"X4-3/4" MULTI MATERIAL From the Manufacturer The Irwin Tools 4935109 Multi Material Drill Bit 5/16-Inch is designed to drill into a variety of materials. These bits will drill in brick, block, tile, metal, wood plastic and marble. The brazed carbide tip has a unique diamond ground 4-face design for excellent centered starts with little walking and best hole quality. The special Grind angle creates sharper tip edges for Fast starts in tough materials and the double ground flute ensures fast and efficient removal of the drilling dust and prevents clogging. The multi-material but features a special duo tone surface finish that reduces friction and resistance, therefore increasing bit life and drill battery life.