Each turn is three days, each hex is 3.2 kilometers, Allied units are Brigade, Regiment and Division. German units are three Tiger Tank Battaltions, Regiment and a few infantry Divsions. Cobra is one of my favorite games. Planning is important to win as the Allies and a crystal ball when playing the Germans. More than half the map is Hedgerow country.
Hedgerow is one column shift for defense and stops advance after combat after one hex.
Other terrain such as Heavy Forest, Hills, Minor and Major Cities give column shifts to defense. The Major City of Mortain gives 6 shifts to the defender. German HQ units give a column shift for offense and defense. German Tiger tank battalions give a column shift on attack. Allied attacks are restricted by supply.