... 1 m to 6 m. 2, Factory Supply directly. 3, Widely usage: quarry, ore, tunnel. Detailed Product Description ... drill bits 1. competitive price 2. high quality 3. factory supply directlyThe drill pipe specification:1, Drill Bore ... Diameter: 40 mm2, Size: B22 (mm)3, Drill pipe length: 0.5 m, 0.8 m ... We specialize in drill rod, drill bits, DTH hammer, air compressor,air hose for over 10 years. We ...