The add-on requires the original version of Spintires. Both machines are equipped with Geiger counters - the action takes place only a few years after the Chernobyl accident, so monitoring the radiation background is vital. It will add a Chernobyl-inspired map and two new trucks, the B-157 and B-505.
Spintires Chernobyl is an add-on for a third-person realistic off-road driving simulator that will send you straight to Chernobyl.