Exploring Valve Archive, part 1. valvearchive.com>archive>Portal>Portal>Art>portalgun.jpg This image appears to depict early design concepts for the portal gun, showing different white casings, alternative moving parts, and what seems to be a prevalence of wires hanging from the handle section. Edit: The image originates from the official Portal 2 Collector's Edition Guide, a book which I would very much like to get my hands on.
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