Is this maybe a Prototype?

[MattyXB]

Here the auction (only in germany):

Atari 2600

It looks like an EPROM (the game in the front), but can't see it good enough.

 

The seller says its a helicopter game with shot the enemys. But the game in the back looks like Chopper Command, maybe he means this?

[Lost Monkey]

Wouldn't a game on an eprom need a hex inverter? It doesn't look like there is one on that PCB. That could be a little sticker on the chip and not a window.

[Tempest]

Doesn't look like a normal prototype. It looks more like a homemade item. I cant be sure from the picture though.

 

Tempest