Core Drill Rod 1.We are manufacturer 2.AQ BQ NQ ... ,AW,BW,NW,HW Drill Rod 4.Tapered Drill Rod Core Drill RodDrill Rod & Coupling (AQ,BQ,NQ,HQ,PQ Drill ... from cold drawn seamless steel tube. Coupling are machined from heat treated alloy steel to withstand wear and stress to which ... request. Left hand threaded rods are available to special order. Core Drill Rod & Coupling