This video shows how to install a rotary dimmer switch in an Outdoors RV 280KVS travel trailer, replacing the existing on/off switch. I replaced the switch for the light over our dining table with a rotary dimmer switch.

You can find the parts needed on Amazon:

12VDC Dimmer Switch for LED RV Lights: https://smile.amazon.com/gp/product/B...

WAGO LEVER-NUTS Wire Connector Assortment:
https://smile.amazon.com/gp/product/B...