*8 inch Max Drilling Diameter: Our core drilling machine generates extreme power because of its 3980W copper motor. Maximum Speed: 750RPM. Maximum Coring Diameter: 8""/205 mm. More importantly, the 4.25""/108 mm core bit in the picture is included. *Durable Construction: As the machine will work upside down, so water would unavoidable flow on to the drill machine. In this case, our drilling rig has a rustproof steel forged output shaft and waterproof copper water inlet for a long-lasting water supply. *Thoughtful Security Design: We also provide overload protection system and an upgraded cooling system. They are designed for avoiding burn-in and prolonging the service lifespan of the drilling press machine. *Ergonomic Handle & Stable Base: It features an ergonomic handle and large base support for effortless drilling or getting oblique holes. The aluminum guide rail makes the drill rig's movement more smooth and accurate. *Wide Application: The wet diamond core drilling rig can be widely used in drilling reinforced concrete, red brick, marble, and other materials. It is perfect for installing air conditioners, pipes, stair railings, and repairing highways, etc. *Specifications Supply Voltage: 230V/50 Hz Rated power: 3980W Drilling capacity: Max. 205 mm / 8 inches No-load speed: 750 U/min Arbor size: 1""UNC Drill bit: 108 mm / 4.25 inches *Pakcage Content 1 x 205 Driller 1 x Diamond bit 1 x Box spanner 1 x Monkey wrench 1 x Air tube 4 x Carbon brushes 5 x Screws 1 x English manual