From the publisher:

Finest Hour
A complete Battle of Britain supplement for Bag the Hun, including full details on the squadrons that took part, mechanisms for generating pilots, squadrons, and scenarios. A comprehensive section looks at the tactics of the conflict, as well as providing full details on where units were based during the conflict. Finest Hour allows the gamer to re-fight the entire Battle of Britain day-by-day, for his pilots to develop and gain experience and even awards for their flying exploits.