The Sentro 40/48 Handle Adapter will help you turn the handle with a drill so you do not cause damage to your hand or wrist. Have you ever had to do 50 – 100 knit rows on your Sentro Knitting machine? It can really hurt your fingers, hand or wrist. The only answer to this problem is an adapter. The adapter has two parts: a 3D printer made cover for your handle and a bit to fit your drill. Just put the cover on your existing handle, insert the bit into your drill, and attach the bit to your cover. Please do not go super fast with your drill, you might get dropped stitches. Go slowly to find the right speed to fit your machine. It also takes the monotony out of turning the handle. Keep an eye on your row counter on the Sentro 48. A reminder: the Sentro 40 does not come with an adapter. You can either count the rows or purchase a row counter on Amazon.