Battery holders for AA and AAA types

Those are battery holders with integrated wire connectors for AA and AAA batteries. It is partly a derivative of http://www.thingiverse.com/thing:9805 . The electricity from a battery is conducted to wires through M3 countersunk screws and M3 embedded nuts. Wires are fixed between holder connectors and embedded nuts. A battery holder can be mounted using two M3 countersunk screws. There are several holder models published both for AA and AAA batteries. Their filenames start with a battery type followed by an amount of batteries in a holder.