The BowStopper Device is an educational device designed to advance and develop in the novice string player excellent bow skills and control.  It is a snap-on device that clamps onto the bow without adding additional weight or affecting the stroke of the bow.  It forces the string player to restrict movement beyond a certain point while automatically teaching the student bow distribution.

In the past and even in this present day, violin teachers are using rubber bands to teach their student(s) to use the tip, middle and the lower part (close to the frog) of the bow. Other music teachers wrap masking tape around various parts of the bow to help enhance bow distribution.  Their teachers are just trying to  help their students, but these aren't the most effective ways.

The problem with rubber bands is that the rubber band and fingers come in contact with the bow hairs, which are not permitted. Its virtually impossible to place the rubber band on the bow and adjust it without coming in contact with the bow hairs. When most people hands, especially children, touch the bow hairs, it leaves an oily, dirty, gritty and grimy residue and prevents the rosin from sticking to the hairs of the bow.  It  doesn't matter if its horse hairs or fiberglass; the sound is affected because the bow literally slides off the strings.  Instead of a good quality sound you get an awful sound or no sound at all.