DieHard battery cover

This is a battery cover for a 19.2V DieHard rechargable battery for the line of power tools. The contacts of the DieHard battery are recessed, so this isn't as necessary as for the Ryobi from which I remixed this. But I think a cover might keep gunk from getting in.
I designed this for my father-in-law; he has Sears power tools that I think are the DieHard 19.2V series. (I happened to find this battery in the recycling bin at my local Lowe's; it was convenient to have an actual battery to test out.)
The Ryobi cover actually fit pretty well, but it was a bit small: I used the slotted version, and the slot widened a little; I figure this will eventually fatigue the plastic. Also, it needed a slot on a different face to fit properly because the DieHard batteries have a ridge on the shaft. I've uploaded two versions; the _1r version has one internal rib and the _4r has four. The ribs taper as they come up from the bottom, so they only grab the battery when they're on all the way.