Hitachi 725713 Two-Piece 1-3/4-Inch 6 Teeth Lightweight Hollow Core Drill Bit with Internal M16 Thread 1-3/4-Inch 6-teeth lightweight hollow core drill bit; internal M16 thread For use with heavy-duty hammer drills and SDS-Plus rotary hammers (6) carbide tips provide high speed penetration Ideal for drilling into masonry, aerated concrete and natural stone Comes with a 30-day limited warranty High Quality Carbon Hardened Steel High Tolerance milled shank provides perfect fit CNC Controlled manufacturing ensures 100% quality consistency