Electric razor

The invention of the thin-bladed disposable safety razor by King C. Gillette in 1900 made wet shaving a lot easier and less bloody than with the folding straight razor. A further improvement, in 1932, was the electric drive of the razor blade in the SIRAMA shaver.
In the Siemens Rasier Maschine (SIRAMA), a standard Gillette razor blade vibrates inside a nickel-plated handle. The 110 Hz vibrator mechanism is an electric motor located in the stem of the handle. It is connected via a lead to a flat 4.5-volt battery in a Bakelite box and can be hung in a holder on the bathroom wall.
To start the motor, the shaver handle must be given a sudden twist with a flick of the wrist.