Get Dad a gift he will really like! Give Dad the Impact Improver - it is a way to practice his golf swing indoors when he can't get to the range.
The Strike Balls are great. You can use them with the Strike Shield to see where your contact point would have been. Then you can take the strike shield off and just swing at the Strike Balls. They will fly some and won't mess up an paint on the walls or hurt anything. This is a great tool to supplement your driving range/course time.
Buy one Impact Improver - and get a dozen Strike Balls 50% off.