Used 3 times. Just stopped working

It works well for my kid’s kiddie pool, it helps the water not be so cold

Nice quality, good to heat small area of water, not big enough to heat my jacuzzi bath tub.

uselessreally useless

If you are looking for something to keep your tub warm while you're in it, or anything like that you will be disappointed. I in fact looking for it for the exact reason that it is made and it worked just fine! I heated up the water in plastic buckets and had no problems with the plastic melting. If you read the instructions, it will let you know that plastic buckets are an acceptable item to heat water in with this device. If you touch the water with the rod inside, you clearly have not paid attention to any of the directions. There is about 8-10 different places that tell you not to touch the water with the rod still in, not to touch the rod itself after turning on, and they even send you a digital thermometer to sway you from touching the heater. This is a good thing to have on hand when there is no hot water, like if a storm wipes out your power, or you are camping, or for any other reason. I used it and it works as it is supposed to work. The water heated within 5 minutes, and I had no issues. Definitely a great thing to have on hand!

The box states "next generation security upgrade", though I confess that I cannot figure out WHAT they are talking about there, but I suppose this goes along with the one-page manual which reads with a chuckle, too.This is an immersion heater, not a security device. Unlike some where you have to suspend the top of the unit above the water, this one is designed to be entirely submerged in water in order to work. While this may reduce its usability in warming a bucket of water, it works perfectly for my use case -- to leverage my excess solar electric production to warm my pool water instead of using my gas heater.The cord is short, but serviceable, and I used a 12-gauge extension cord to feed it power from the socket to my poolside deck. From there, simply drop it in (so it is not touching the side of the pool) and plug it in, and leave it alone. (I may decide to build some sort of prop to help it stay in the center of the pool, but right now I'm using a scrap of wood as a way to keep it away from the pool side.) The docs say not to run for more than 3 hours at a time, so I've been running it for 2-3 hours, unplugging for an hour or two, and then plugging it back in again. When active, the power circuit jumps by approximately 1600W. While this is a bit higher than the rated 1500W, I expect that heat generation by the 25' extension cord is also factoring into this. In any event, you want to take care to keep other devices off of this circuit when in use to avoid tripping a breaker, and use a heavy-duty extension cord, too.The included thermometer is simply an LCD panel with temp probe, and not integrated in the unit at all as a thermostat. As such, if you are trying to heat a small amount of water to a set temperature, this may not be for you, as you will need to monitor it on your own. In my case, though, heating 23000 gallons of water is going to occur very slowly, and I'm not worried about timing it. Two button batteries come preinstalled in the thermometer, so you'll want to remove them for storage if you're not using it. (I am thinking about re-purposing that for a freezer temp monitor, instead.)The scrap of sandpaper and silver ball of curly "stuff" had me stumped, and it was never mentioned in the instructions, though the listing here calls them cleaning tools, so I suppose if the unit starts to get crusty, you could use that.[Edit] Just 10 days after I started using this, limiting my usage to 3 hours at a time as directed, the unit now trips the ground fault breaker as soon as you plug it in -- either wet or dry. Lowering to one star and attempting to contact the seller for info. Stay tuned![Edit] The seller replaced the defective unit, so I am raising this back to 3 stars for now. However, the pool is now up to temp, so I won't be able to test it in earnest until the fall.[Edit again]The replacement heater failed in the same way (ground fault) after less than 4 hours of use. It seems that they have an issue with the waterproofing around the top of the unit. If you let it dry out completely, it powers up just fine. However, after immersing it in the water again, it runs for only a few minutes before it trips the GFCI. Yet the unit cautions you that you MUST have the entire thing immersed to avoid overheating. You can't have it both ways. Stay away from this design.

Included with the package you have a small scrubbing pad, an LCD thermometer and the heating unit itself. The unit works ad advertised in that it does heat up the water. You need to keep the entire unit immersed. Plenty of cautions for you not to stick your hand in the water while the unit it turned on and heating. You unplug the unit first. You also need to plug it into a dedicated outlet in the event of what I could imagine would be a short, if that were to happen. Where the unit falls a bit short is that you have to constantly monitor it. It warns you should not have it on for more than three hours. What would have been nice it to have the unit integrate with the LCD thermometer where you would be able to set a temperature and have the unit turn itself on and off to keep the temperature constant. This way, you can walk away while it is heating the water and come back when you are ready to use it and it's at the expected temperature. Otherwise, you have to keep physically monitoring the unit. The unit works as advertised otherwise.

This is a simple but well built appearing heater. When you plug it in, with the heater fully immersed you immediately hear faint boiling noise and depending on the angle of the element, small bubbles rise out of the vent holes, although those disappear before they rise more than a few inchese. For a bucket of water with 3 gallons of cold water in it, it raised the temperature 20°F in five minutes which roughly tracks to the rated 1500 watt heater. The digital thermometer comes already on, which is fine, I expect those two LR44 batteries to last a couple years. The units were in Fahrenheit and I off hand didn't see any mechanism to switch it to Centigrade but I did not look closely. I do wish the body of the thermometer was waterproof so you could leave it by the side of whatever you are heating but I presume the thermometer would stop working if it gets wet.One enhancement they could have made is to have a GFCI circuit breaker in the plug to protect those folks who would be unwisely plugging into a conventional outlet. A GFCI circuit basically shuts off the circuit if the electricity coming back doesn't exactly match the electricity going out, i.e. if it is going elsewhere like into the water (or someone's body). So it's a basic safety feature you want and that all bathroom and outdoor outlets are supposed to have, but all to often in non-new homes might not have.That said, it's a good price for a heater that would be handy to chuck into small pool, or bathtub when no one is in it to heat or reheat the water to a comfortable temperature.