· · Suitable for sampling in concrete, cement, brick or bituminous pavement, or for drilling in pipeline works. · Powerful and high-speed series motor. Fine-machined transmission mechanism and superior laser-welded diamond bit ensurefast and correct penetration of granite, reinforced concrete and bituminous pavement. · Dual insulation, dual protection and water-tight switch ensure safe, normaland fast operation. · Technical Specifications: Drilling Range: 15-300mm Rated voltage: 220v Rated input power: 3900W NO-load speed: 450r/min