This is an official but limited cartridge release of the game Volley for Two for the Commodore 128 by kollektivet.nu.
To our knowledge, this is the only game that has ever been released on cartridge for the Commodore 128.
It does NOT work on a C64 and it is a two-player game so you must have a Commodore 128 and at least one friend to play this game. There is no single-player mode.

It uses both the screens on the C128. Gameplay is on the 40-column screen and the 80-column screen shows the scoreboard. You don't need to have an 80-column monitor connected to play the game as all the action is on the 40-column screen. It's just a bonus if you do.

Credits:
Jonas Hultén (programming)
Mikkel Hastrup (music and sound effects)
Anders Larsson (graphics)
Per Bengtsson (cartridge hardware design)

Read about the game at https://kollektivet.nu/v42/