Feature 1With seamless steel pipe design, has a longer life, can be well balanced in use, and is not easy to deform 2The seamless steel pipe sintered with highquality diamond powder is more tough and durable 3Simple to use and easy to replace, it can meet your needs and ensure your operating efficiency 4Equipped with concentric shafts, drilling faster, and the drill bit does not deviate from the center during work 5Compatible with a variety of equipment, suitable for handheld drilling rigs/benchtype drilling rigs Item Type: Diamond Drill BitsWall Thickness: Approx. 4mm/0.15inDrill Body: 45# Seamless Steel PipeKnife Tooth: Flat ToothDiameter: Approx. 18mm/0.70in, 20mm/0.78in, 22mm/0.86in, 25mm/0.98in, 27mm/1.06in, 30mm/1.18inLength: Approx. 370mm/14.6inTooth Characteristics: Top Flat ToothEarly Use: Drilling and Sharpening SpeedLater Period of Use: After Using for a Period of Time, the Speed DropsScope of Application: Multi-story Residential Brick-concrete Structures, Engineering Subways, Bridges, Expressways Package List 1 x Diamond Drill BitsNoteWhen opening the hole, first incline 45 to open the small groove, then slowly straighten the drill bit, and make the hole vertically.It is strictly forbidden to use the electric hammer function, and it is recommended to use the electric drill functionPlease note that the the opening number of this product is randomly issued with double openings and triple openings.Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.