This is an interesting piece of medical history. Some ailments were and are treated with ultrasonic vibrations applied to the skin. That is what this device is. A Medi-Sonar made by Dallons Laboratories. The flat part of the hand wand on the right is applied to the affected skin area. The device uses a piezo electric crystal to vibrate at high frequency (Frequency unknown in the high Khz to low Ghz range).

The output power is measured in watts like a radio transmitter, but then it gets divided by the surface area because it is a concentrated emission.

This unit has a weird plug. It is polarized presumably because it was a medical device, as that was unusual for the time. The center pin is ground. The other end of the cord is a normal 3 prong grounded US plug.

The inside of the chassis is fairly simple. There is a very heavy transformer, two tubes to the right of it, one large tube with a clip on top, and a coil. The two tubes on the right are both 5U4 full wave rectifier (RCA) with a possible date code of 1962. The big tube in the middle is a 809 triode transmitter tube. This website has good close up photos of the tube.

This is a promotional booklet from Dallons (found on archive.org) talking about the manufacturing process of the quartz crystals.