20 Litre Solar Shower from Highlander. Ideal for backpackers, camping, etc. Black material attracts heat and in the sun takes about 3 hours to heat up to 41C. It has a reinforced carry handle and hanging cord/hook. Shower head with on off.
To be fair they aren't going to "set the world on fire" but we often used one when we had a trade stand at Game Fairs. We hung one up out the back of the marquee and they were ideal for taking a quick dip under (in your shorts!) at the end of the day to freshen yourself up and our lass used one to wash her hair every morning. Better than the tackling the queue to get into the CLA showers