electric chair
A specially built chair used in electrocution executions.
The chair itself is primarily a restraining device, using several leather belt straps (or similar mechanisms) to keep the subject firmly restrained in the chair. The actual electrocution is done by a helmet-like headpiece, which is worn on the subject's head and connected by a cable to the electricity generator, and one or two other electrodes attached to the subject's legs, which may be built into the chair itself.