Battery cover for wireless keyboard

The battery cover on our Keysonic wireless keyboard (http://www.ebuyer.com/product/104608) broke: the prongs failed resulting in a failed power, lost batteries and intense frustration. So we printed a new, improved replacement cover. Yes, 3d printing can produce something useful!

The original cover was recreated in qcad. The areas that experience most strain were reinforced with ribs or by thickening, while the flexibility of the latch was increased by lengthening the slot in the cover. A