Brand Name: Montana Brand | Finish: Black Oxide | Material: Alloy Steel | Number in Package: 1 pc. | Packaging Type: Clamshell | Shank Type: 3-Flat Shank | Drill Size: 1/4 in. Montana Brand diamond tile drill bits provide outstanding performance in ceramic, porcelain, granite, slate, marble, glass and most all hard surface materials. Drill holes for water supply lines, drains, electrical/wiring, towel bars and fixture installations. | 15X Longer life versus carbide tip spade drill bits | 10X Faster drilling than standard glass and tile drill bits | Patented diamond sintered tip for easy start | Compatible with all corded and cordless drills | Large core ejection slot for easy material and plug removal | Reverse thread spiral for continuous water feed | Segmented cutting edge design for improved irrigation and material evacuation