These nice 12-volt surface-mount LED "puck lights" are merely 3.2" diameter and 0.6" thick!  The satin silver plastic housing is attractive enough to be mounted in visible locations inside your trailer, but they are so slim that they hide easily under cabinets or in closets.

The 12 LEDs inside each puck produce a nice warm white light that is much more appropriate for interior lighting than the cool white light produced by most other LED fixtures.

One of the best things about LEDs is their very low power consumption, an extremely important factor when relying on your trailer's battery power.  These lights draw only 70mA.  That's approximately 1/10th the draw of a single standard 10w halogen bulb.  Yet the light output of 22 lux is approximately 1/2 that of the same halogen bulb.

Available with or without a switch.  The switched version has two red LEDs under the white rubberized switch.  Those two LEDs stay on at all times, even when the light is off.  The red color is designed to be easy to find in the dark without upsetting your night vision. Those two LEDs inside the switch draw approximately 10mA.  That's a very minor draw (1/100th of an amp), but something to consider, depending on your camping habits.

The version without a switch can be wired to a separate 12v switch, making it possible to operate several on a single switch.