Abstract: Apparatus for use with conventional punching, striking or speed bags to indicate the frequency at which the bag impacts the platform from which it is suspended in response to the bag being hit by the user of the bag in training or recreation, includes a switch, mounted on or in the platform from which the bag is suspended, disposed along the impact point loci defined by the bag impacting against said platform, which sends a signal to a frequency counter and display oriented for easy visibility by the person hitting the bag.

Abstract: A dental handpiece having a low noise level consisting of: an elongated main housing having a head portion at the forward end thereof; a drive shaft located within the main housing and supported by fore and aft bearings mounted within the main housing; a rotor/burr holder located within the head portion of the main housing and supported by bearings mounted within the head portion, the rotor/burr holder being adapted to receive a burr drill or the like; an air-driven axial flow turbine wheel located and supported within the rear portion of the main housing, the turbine wheel being operably connected to the drive shaft; and, a coupling system for operably coupling the forward portion of the drive shaft to the rotor/burr holder. In one embodiment of the invention, the coupling system consists of a set of cylindrical driving magnets mounted on the forward portion of the drive shaft and a corresponding set of cylindrical driven magnets mounted on the rotor/burr holder.