For your consideration is one used, tested and working reproduction game.  Works on the Atari 7800, 7800+ and 2600+.
 
Klax is a fast-paced puzzle game in the spirit of Dr. Mario and Columns. The premise is simple: colored tiles move down a conveyor belt at the top of the screen, and you must catch them with your paddle and drop them into the bin below. Line up three tiles of the same color to create a “Klax”—the move that gives the game its name. Klaxes can be formed horizontally, vertically, or diagonally, with each type awarding different point values. Beyond the basics, more advanced patterns can earn even higher scores and may even trigger hidden events.
 
Each wave presents a different objective:
Klax Wave: Complete a set number of Klaxes (any type)
Diagonal Wave: Complete a set number of diagonal Klaxes
Horizontal Wave: Complete a set number of horizontal Klaxes
Point Wave: Reach a target score
Tile Wave: Survive a specific number of tiles
 
Your paddle can hold up to six tiles at once—any more, and they’ll start to fall off. If you catch a tile you don’t want, you can toss it back onto the conveyor by pressing up, though it will eventually return. Every dropped tile lights up a miss counter, and once they’re all filled, the game is over.
 
To help you out, special glowing tiles occasionally appear. These act as wild cards and can represent any color, making them essential for completing advanced patterns like the Ultra Star and Tengen Stax. Use them wisely—they’re rare.
 
Although the Atari 7800 version of Klax is considered one of the best home adaptations, it was never officially released. By the time development was complete, Atari had discontinued support for the 7800, leaving several finished or near-finished titles—Klax included—on the shelf.
 
 
Refund Policy…
 
If I say it works, then it has to work.  My guarantee.  A full refund will be given after the return of the item and confirmation that it is nonfunctional, and no components were “swapped”.  
 
Shipping...
 
Domestic shipping choose between USPS Priority Mail or USPS Ground Advantage.  I reuse and repurpose boxes and packaging materials whenever possible.  This will be shipped in a box.
 
 
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