Indicator and charging panel

Just when the battery is not easily accessible, or - as in my application - is installed behind a partition, this will help small panel to get a clean connection point.
The only suggestion for the manufacturer: a cutting template of cardboard would be a great help to make it easier to mark the cut. So you have to tinker the template in order to mark out the exact cut can. The rubber gasket is for something to elastic, especially when working on a vertical surface.