This is a packaging prototype for the 1991 Wyld Stallyns Speaker & Tape toy from the Bill & Ted’s Excellent Adventure toy line. Engineers at Kenner would create mock-ups of toy packages using whatever spare cardboard they had on hand. In this case they attached a prototype of the speaker and a generic cassette to a 1991 Starting Lineup baseball proof card.
Package samples like this would be used for anything from getting a feel for what the finished product would look like, to testing how the toy would fit inside the plastic bubble.
Close-up of the speaker and generic cassette tape:
Close-up of the production toy:
