Saver subs are in the business of saving. Saver subs are typically attached to the bottom of your top head drive system, or to the bottom of your Kelly bar. These two spots are where your drilling string is made up and broke out most frequently. In other words, this tool receives the most amount of wear. These subs are “a life insurance plan” in the protection, and longevity of what it’s there to take every connection grind for. It’s always great to have an extra saver sub in rotation. While one is in operation the other is getting re-cut, or repaired to avoid down- time. These subs are typically 12 inches or less shoulder to shoulder (SH-SH) and can also be a cross over from one connection to another.