Adamson B10 Bed Cooling System - TWIN 75” L x 39” W - 100% Cotton Mattress Cooling Bed Pad for Night Sweats - Water Bed Cooler Ideal for Hot Sleepers - 5-Year Assurance - Navy Blue

I've been using this for a few months now, and I love it! As per the headline, it's simple and effective. As it works on evaporative cooling, the temperature it cools to depends heavily on the ambient temperature and humidity though, hence the mixed reviews in this regard.How it works (for those inclined), is just a tank of water, a pump and a fan. The pump pulls water from the tank at the bottom of the base station, pushes it through the tube that runs into the sheet, splits into multiple pipes in the sheet and back out of the sheet through the return pipe back into the top of the base. The water flows down over a paper-like filter, which has a fan in front of it. A small amount of this water evaporates which cools the water as it flows over the filter and back down into the tank, to be circulated around again. The controls allow you to adjust the speed of the fan, and how often the fan turns on/off. That's all it really is.But there are downsides (in no particular order):1. You have to top up the water before bed. - No hardship.2. It needs cleaning regularly, which can be arduous. This can be reduced by dropping some chlorine granules (hot tub supplies) in with the freshwater. Note: Don't use bleach or anything, it will bubble up inside the machine causing all of the water to slowly leak out overnight as the bubbles burst outside of the tank and run down the insides of the base. Ask me how I know!3. The fan inside is not *loud* at all but it *could* be quieter. When it fails, I'll probably replace it with a Noctua fan.4. The vibrations from the pump can flow through the pipes and into the mattress, causing a humming sound to reverberate through the bed, which you can only hear when you put your head on the pillow. I resolved this by making sure the inlet/outlet pipes don't touch the side of the mattress where the mattress is unpadded (where the springs are).5. Would be nice if the pipes were a little longer. Could add a coupling and extend the pipes I guess.6. You can feel the smaller pipes within the cooled sheet itself, they are soft and this does not bother me. With the exception that over time with use, the layout of the pipes inside the sheet can get a bit messed up and start crossing over each other causing lumps where they cross, which requires some finagling to resolve and get them sorted out.7. It should really be kept higher than the bed.8. There is no 'temperature sensing'. Ideally, you want to be much cooler at the start of the night, (the body temperature drop helps you to get to sleep more quickly), but then not so cool later in the night. There's no support for this, so it's possible to wake up in the night/early morning too cold! Also, the room might heat up overnight if your door and windows are closed, so you could wake up too warm because you went to sleep on a low setting. I might resolve this one day by hooking the fan and/or pump up to a raspberrypi, with a temperature sensor in the water but for now, it really isn't a big issue.9. The buttons are on the top... but the machine *should* be above the mattress... so you can't see what you're pressing without getting up - Annoying. There is a remote, I've never used it though so I can't attest to its usefulness or complain too much. The raspberrypi solution would resolve this issue.10. Mine came with a US standard plug. So I needed to buy an adapter.These all probably seem like they amount to a lot of bad things to have to put up with, but honestly, the only reasons this didn't get 5* is the lack of a temperature sensor and the cleaning routine.I use this every night and for the price, it's an absolute dream. The cost and simplicity of repair make it well worth it over other solutions such as paying for an 8Sleep subscription. or having your bed sheet moving about with those that blow air through the sheet.