That, I believe, is a radio station cart.

You got it! The label has been ripped off, so I don't know what's on it..maybe a commercial I did.

Water audio :D

For underwater recordings.

Looks like a case to put a camera in for under water. :P

4 track! :D

Nope.. most radio station carts were 1 track for mono or 2 tracks for stereo.

The carts used for the 4-track home system were the same Fidelipac carts as radio station carts...The machines have a pinch roller which pops up out of the machine like a broadcast cart player.

Radio station carts either have two tracks for mono or three tracks for stereo...Mono carts have an audio track and a cue track and stereo carts have a left, right, and cue.

Lol it's an 8 track...

Or 4, It's missing the top right spindle 8 tracks have.

It's a 2-track for Radio stations

Ya saw that above ^^

Ah yes, the old radio station carts. When I first went to college, all of the playback devices for radio were replaced with computers and hard drives, and the old Denon Cart CD players.

The CBC used to put sound effects on carts for shows like the Royal Canadian Air Farce (back when it was a radio program) and the Frantic Times. I've seen some behind-the-scenes footage from both programs, and the sounds were actually mixed in live while the program was going on, and some sounds were played off of the carts. Still cool to look at though!