The adapter set includes 8 specially cut tiles which allow you to combine front and back sides of existing Zpocalypse tiles in the same game. In addition, there are 8 flat sided adapters, which allow you to use Zpocalypse tiles with non Greenbriar games tiles for your own custom zombie/wasteland themed games. The 8 double sided Zpocalypse tiles feature a Road on one side and Toxic River on the other.