Circuit Playground Proto Gizmo Adafruit Circuit Playground Proto Gizmo is used to extend and expand Circuit Playground projects with a bolt on Perma-Proto. This PCB looks just like a solderless breadboard but has permanently affixed M3 standoffs. These standoffs act as mechanical and electrical connections. Solder to the gold-plated traces to create custom inventions. Each pad of the Circuit Playground has a large oval pad, and in the center, a blue-marked Ground rail and red-marked 3.3V rail. The center has side-connected groups marked in black on top. Fits both Classic and Express Circuit Playgrounds, but the oval pad markings match the CPX pad naming.