... ,AW,BW,NW,HW Drill Rod 4.Tapered Drill Rod Core Drill RodDrill Rod & Coupling (AQ,BQ,NQ,HQ,PQ Drill RodEW,AW,BW,NW ... ,HW Drill Rod )Geotool drill rods are ... on the following specification table all drill rods are manufactured with a parallel wall.Old Series drill rods E,A,B,N, are ...