It's the cover for the box to my first ever model that I bought and put together - the "Star Trek" exploration set. It included a communicator, a phaser and tricorder that you could put together. They were great toys to play with as a kid (I was 10 and bought it the summer of 1976)...except eventually my communicator flip top broke, my dog took the phaser in his mouth and carried it off (crushing it in the process), and the tricorder I later put a radio in.
Later in life I replaced all of those toys with better quality models - models that you also loved to play with as a toddler and preschooler! You'd pull the tricorder over your shoulder and carry around the phaser in one hand and the communicator in the other. We'd go on a "landing party" of our own and play "Star Trek" in the house!
