Simple box for generic PWM controller. I use mine to control dew heaters / flat panel brightness on a telescope. All of the electronical components are generic parts from ebay.

On the lid there are holes that fit 12mm button, 6mm PWM knob and 8mm RCA connector. Ive also included a lid without holes so you can make your own. I advice to glue the lid in place with a dap of superglue although pressure fit might work on it's own too.