You know, putting these schematic diagrams of some of their top technology on a shirt might not be the best way for the Resistance to keep these sorts of things a secret. We all know what the Rebels having the plans to the Death Star did. And the exhaust vents on the Millennium Falcon are clearly marked on here. Just a bad strategic move all around, guys.
Schematics of BB-8, the Millennium Falcon, and a Speeder.