The electric chair/fruit machine combo was a deathtrap that, according to the Joker, was built by the One-Armed Bandit Novelty Company at the request of "a whimsical Caribbean dictator".
The deathtrap functioned much like an ordinary electric chair: victims were strapped inside, and a helmet connected to several electrodes was placed on their heads. The helmet would then deliver fifty thousand volts of electricity through the victims' bodies.
What made the device unique, however, was the fact that it was connected to a slot machine. It would only deliver the fatal current if the slot machine was activated, and all three of its reels stopped on the "Lemon" symbol. According to the Joker, all three reels stopping on the "Orange" symbol would grant the victims freedom, while all three reels stopping on the "Liberty Bell" symbol would grant the victims not only freedom but also fifty thousand dollars in cash.
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