M/F drill steel is an alternative to couplings sleeves to include the female part of the threaded connection as an integral part of the drill steel. M/F drill steel provides more rigid connections and is easier to uncouple and handle. The service life also tends to be better than with separate couplings. The advantages of drilling with M/F steel include: easy handling, quicker uncoupling, tighter connections, the potential to drill straighter holes, and longer service life.