I have two 25 watt
panels, mounted directly on a
cabin top. They do what they claim to do. Thin, small, light, you can walk on, at least step on them. Basically it is thin sheet of aluminum with
solar cells It is covered with very hard transparent nonskid material. There are several holes on sides. You can bent the
panels slightly. Mounting is simple - just bolt it or screw it to
a surface.
Electric output is OK. I'm getting 11-12 amps a day on average in summer time in NY, out of 50 watt. it is fixed panels on a
deck with some shadows from boom and masts at times.
I'm satisfied so far and thinking of adding another 50 watts of very expensive panels. Hard to beat mounting options although.