A violet ray or violet wan is a device used for the application of low current, high voltage (min 10kV to max 50kV typically), high-frequency electricity to the body using a Tesla coil, originally sold as a supposed medical device claimed to be useful in electrotherapy, though, since the 1990s, it has been used by some into BDSM sex as a sexual stimulation device and by hairdressers to stimulate the scalp. It is especially popular among the BDSM community though antique models are also popular among collectors of historical or quack medical devices. The violet ray was recommended by Edgar Cayce. Today, it is also used, with different electrodes, for electrostatic leak detection. Chicago Police Department detectives working under Jon Burge are alleged to have used a violet wand to torture suspects in the 1970s and 1980s.