Diamond section 19/16” used with 111/16” Rotary coal drill bits as per B.S. specification 2593/1964 for dry drilling and fast penetration in friable material
Turbine section 19/16” drill rod up to 6” used with 111/16” Rotary stone drill bits as per B.S. specification 2593/1964 for wet drilling in abrasive Rocks.