The construction is very simple. The connection for the coil on the charger must be unsoldered and extended with a cable about 10 cm long. The coil is glued into the upper hole. Aftert the cables can be pulled through the inside and then soldered back to the board. The board can then be snapped into place and the connector protrudes perfectly from the back. Finally, the holes are sealed with the two plades. There is also space for anti-slip pads on the underside. 

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