An activation box is a rectangular lightsaber component that’s typically located within the middle of the lightsaber hilt or possibly a bit toward the pommel of the lightsaber hilt. An activation box is most commonly associated with Original Trilogy lightsabers, including: Obi-Wan Kenobi’s lightsaber, Darth Vader’s lightsaber, and both of Luke Skywalker’s lightsabers. Some custom lightsaber companies do use activation boxes in original designs as well (e.g. Electrum Sabercraft’s Remnant Smart Saber features a low profile activation box).
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Where did activation boxes come from? The very first Star Wars lightsaber, the Skywalker lightsaber, was fashioned out of Graflex flashgun. The Graflex flashgun’s clamp area contains the rectangular shape that we now know as the activation box.
A lightsaber activation box typically contains some type of card: most commonly a clamp card (circuit board design) or a bubble strip (an Exactra calculator replica). Slothfurnace is a well-known lightsaber clamp card maker and Roman Props and Wannawanga are two bubble strip vendors.