.....but there is a learning curve to consider with this amazing invention. I want others to get as much satisfaction out of this purchase as I do, so sit down; this is a long one. I will try to put into words what I have learned. Not in any particular order, but here goes:First off, I purchased this unit with the larger size spread 160x140 cm, which happens to be almost the exact measurements of my mattress (I made sure to take mattress measurements prior to purchasing this.) Living in south Florida, the temperature here is HOT. All year long. 90-95 degrees Fahrenheit in the middle of November, hot. But I digress...Opening the box, this unit does come with a few extra pieces that seem to have no function, nor does User Manual explain what those pieces are for. So, those pieces are now relegated to my junk drawer until I figure that out on my own in an "Aha!"-moment what they are for.There are two long pipes attached to each other in tandem which connect the spread to the machine. One is the artery, the other is the vein (think of it that way). I mention this because...and here's lesson #1...when you are connecting these pipes to the machine and to the spread at the other end, at first it seems that the pipes are too narrow to fit over the fittings. Don't panic. You just have to wriggle with it and, almost miraculously, the pipe endings will stretch just enough to allow a very tight fit. Okay. Disaster averted.There is an electrical cord to plug into the wall and into the machine. That's simple enough. Plug it in.Now comes the task of filling it with water. On the machine, you will see 2 windows-one in the front and one in the back-where you can see the water level inside the machine. When doing this for the first time...lesson #2...you must turn the machine on FIRST, as this will pump the water into the spread. As mentioned earlier, I bought the larger size, so I needed well over a full gallon of water to inflate the spread with the adequate amount of water to operate. Keep in mind, the machine will give a message on the display [E1] if the water level is too low. When you get this E1 message [and you will] just turn it off and on again to clear it. By the way, it is perfectly fine to use regular tap water. You don't need to buy purified water.Now, one thing that is included, though not pictured, is a bucket for the machine to sit inside of. This brings us to lesson #3: this bucket is absolutely essential, as it is near impossible to pour water into without some spillage overflow. Also, there will be some backfill which will end up in the bucket. Don't panic-this is what the bucket is there for.By the way, "Aha!" As I am writing this review, I figured out what those "extra pieces" are for: those pieces are needed for storage if you are putting the unit away for the cooler months when you might not need to use it. [As there is no such time here in Fort Lauderdale I won't be putting the unit away. Ever.]Here's one word of advise...HEED MY WARNING HERE... Do NOT use Bleach [or any other bleach/chlorine-based water cleaners out there in the market] in an attempt to clean your unit water, under any circumstances. Bleach is very corrosive, and will cause the delicate cooling filaments in the unit to disintegrate. I mean, LITERALLY disintegrate. Once this happens, your system is utterly useless. Trust me; I learned this the hard way. I had to replace mine when I made that mistake. And those other so-called water cleaners and sanitizers on the market simply do not work, and cost too much. I am able to keep the water clean now [in my new unit] by draining it and cycling the following refill to include a 16oz. bottle of rubbing alcohol, once a month. Personally, I use the green kind because it smells better. Personal preference, but regular clear rubbing alcohol works, too.But, enough of my pontificating. You probably just want to know if this thing actually works or not. The answer to that is -- in 1 word -- YEEEESSSS!!! This is by far the best thing I have ever bought. I now sleep all the way through the night without waking up drenched in my own sweat. Not even once. It works so well that I don't run the air conditioner at night anymore. I am now officially spoiled, with all of the great sleep I'm getting now; I don't even know how I was able to go so long without this unit! I'm quite sure that I will own one of these units for the rest of my life. Seriously. No hyperbole there. The next time somebody asks me "How much is a good night's sleep worth?" My answer will be "$175.87+tax with free shipping!!"Good night, and sweet dreams!P.S. Just in case you might be asking the question that you would never dare ask, I'll go ahead and answer it: You and your partner CAN do your...how should I put it... nocturnal activities(?)...skipping through the cabbage patch(?)...horseback riding(?)...horizontal tango(?)...you know what I'm talking about...without removing the mattress pad. It is durable. Have at it.