Subs are used to connect the various components throughout the entire drill string - from the drill bit to the rotary head. They provide a variety of functions such as changing from one thread form to another (cross-over subs), or reducing wear to the threads of components (thread-saver subs).

Using special alloy material, all subs and adapters are manufactured to the same high quality standards as Sandvik drill pipe. Sandvik rotary subs are available as bit (bottom) subs, top (spindle) subs, cross-over subs and thread-saver subs.