Male/male extension rods from Crowder Supply connect your rock drill to the bit across every common thread system: R25, R32, R38, R51, T38, T45, T51 and H55. Rods run from 8 in. to 288 in. on hex and round bar stock from 7/8 in. to 2 in., for extension drilling in mining, tunneling, tiebacks, geotechnical work and construction blast-hole drilling.
Extension strings are built joint by joint — shank adapter to rod, rod to coupling adapter, coupling to rock drill bit — and every joint wants the same thread system and bar size. Male/male rods are threaded male on both ends and join through a female/female coupling; if you want rods that stack directly without couplings, see our male/female extension rods. Crowder Supply stocks rods from Brunner & Lay, Mitsubishi, Rockmore, Sandvik and Epiroc, and the guide to choosing drill steel and rock drill bits covers matching steel to your drill and ground conditions.
- Thread systems: R25, R32, R38, R51, T38, T45, T51 and H55 rope and trapezoidal profiles
- Lengths from 8 in. through 288 in. to build any practical string depth
- End configuration: male/male, for use with female/female coupling adapters
- Bar stock: 7/8 in. hex, 1 in. hex, 1-1/4 in. hex, 1-1/2 in. hex, and 1 in. to 2 in. round sections
- Brands stocked: Brunner & Lay, Mitsubishi, Rockmore, Sandvik and Epiroc
- Applications: extension and production drilling, tiebacks, geotechnical, oil & gas and environmental drilling
- Stocked by Crowder Supply in Denver in the popular sizes
