I have Rigid rock lights on my trailer and love them. I believe they are the
Rigid 40020 in the
A series. Lots of light, cool white, 3watts, low 0.2amp draw.
A little side advantage to having rock lights under your vehicle or trailer is that when camping around a lot of flying insects, I just use my rock lights to light up camp and all the bugs stay low. That and one other light on a pole away from camp and it is a much more pleasurable night. Last time I did that, though, I ended up with flying ants crawling up my pants leg a couple times. Imagine a full grown man hobbling around with his pants down trying to find that damned bug in his pants.
Be glad to show you images if you really want them. Looks like most other trailers with rock lights. And, I think you only need four for most applications, though they sell kits with six, maybe more.
I'll be adding a set to my van when I do the dual batteries.