<p>This Microvision handheld game includes the Block Buster game cartridge.  Microvision was the first handheld game with interchangeable game cartridges. The game has a small 16x16 monochrome LCD screen with a paddle wheel controller. 
</p><p>Each game cartridge has its own CPU and keypad.<br></p>
A good source of information on vintage handheld electronic games is the Electronic Handheld Game Museum (<a rel="nofollow" class="external text" href="http://handheldmuseum.com/">Handheldmuseum.com</a>).
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/51764518@N02">Joe Haupt</a> from USA
CC BY-SA 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/51764518@N02/13066866233/">Vintage Microvision Cartridge Based Electronic Handheld Game By Milton Bradley Electronics, Model 4952, Made In USA, Copyright 1979</a>