There are several brands of portable hot water showers available with different water flow ratings. The smallest camping type hot water shower unit from Camplux with a 5L flow rating will provide an ample flow of water for a shower or for washing the dishes when out camping. They can also be convenient for use around the home for a warm rinse after a swim in the pool, or for washing pets or washing down outside areas. They are designed to be purely portable, and so they can be quickly connected and transported on a two wheel dolly for immediate use anywhere hot water may be needed.This 10L hot water unit is somewhat dual purpose since it can be used as a portable under certain conditions but is more intended to be mounted as a permanent hot water unit with a professional installation. A propane regulator and hose connection is not included for this unit since the plumbing will be stationary. The piping will be more complex for permanent installations but when connected correctly will allow this little unit to behave with the same fury as a 150 gallon central water heater, all at a fraction of the cost. Just be sure there is an adjustment valve situated within reach so each individual using it is able to fine tune the temperature of the water to perfection. Otherwise, expect to be showered with a never ending flurry of complaints and gripes that your stupid shower doesn't work right. Not my favorite impression to be standing there wet and freezing and no hot water.Understanding the basic principles about what is required for these units to work properly will help achieve successful results. Operation is rather simple so many won't even take the time to understand fully just exactly what happens or what is needed when attempting to set up a hot water shower.1. These units only have one water inlet for cold water and only one water outlet for hot water. There is a connection for a propane gas supply. When you connect gas and plug in the electric power (other units use 2 12V batteries), it will begin heating the water when it senses the water flowing through the unit. Thus, if either the gas or power is not turned on, the flowing water from the outlet will not be heated.2. The heated water is relevant to the temperature of the water flowing into the unit. Very cold water flowing in will be heated sufficiently, but if the water flowing into the unit is already warm, then chances are that the heated water will be so extremely hot it may scald someone when attempting to use it if there is no means to mix cold water with the hot water. If the water flowing in is warm enough for a shower, then just leave the power off.3. Gas fired hot water shower units mounted indoors must be vented to the outside.Understanding these three principles is necessary before attempting to plumb a tankless hot water shower that works well for everyone using it.By the way, Camplux no longer states on the Amazon page that there is an automatic 10 minute shutdown timer safety that cannot be disabled. Apparently people were getting freaked out at the thought of their showers shutting down before they were finished. At least I couldn't spot any such statement the last time I looked for it. There are some recent comments about it now being 20 minutes. I tried to contact their support for clarification about that by email and got back a message that said Amazon was at fault and they wanted to know the number of the part I needed, which clearly indicates how well they have perfected understanding English. If I didn't already have good results with my Camplux shower I think after that reply I would have just looked at another brand. In any case, after a year of using the unit, it continues to perform perfectly and the safety has never caused a shut down while I was using it. If it ever does, just flipping the power switch off and back on again resets the unit and the blessed hot water shall be wondrously replenished.The basic camping units simply provide one hot water outlet and need to be mounted in an outside area with good ventilation. With such a basic principal behind using a portable hot water shower, one has to wonder how things can go so terribly wrong for others when attempting to use your perfectly operating little shower. Well they do, especially when not really savvy about the principles that allow these showers to operate. Shower units like these are sometimes used as seasonal installations in hunters cabins out in the woods where some, but not all utilities exist. Having a little gas operated water heating device is a really nice convenience, provided there is a means of flowing water and electric power to run it. If not, then Camplux has a pump that operates on 12 volts or there are many others available that can also be powered from a portable generator and will provide adequate water flow from a tank of water. There are a vast number of simple to complex portable shower units specifically designed for this purpose available as well, so it is best to check some of them out as to which unit best serves your needs. My backup shower runs on 12 volts and pumps water from a bucket with about the same force as my Camplux. So simple.Regardless of the requirements needed to get the shower operable, the temperature of the water flowing out will always be influenced by the temperature of the water flowing into it. That may explain why there are suddenly complaints that the water is too cold as summer temps begin to subside. Although most water supplies have a consistent temperature year round, there are some cases when it will vary according to environmental temperature, and even depending on what time it is on a nice sunny day, especially when using a garden hose to supply a purely portable unit. Remember that more water flow tends to have a cooling effect even though the amount of heat remains constant. In a one outlet system then, the flow of water that may be too hot can be reduced in heat simply by increasing the flow of water without ever reducing the flow of gas. Placing an adjustable valve at the shower head will allow for variable water flow, and it works wonderfully. So if none of this makes any sense to you, then better have a professional install your shower with all the bells and whistles according to local codes.