Review on O2COOL 5-inch Portable Fan Battery Operated, 1 Unit, Grey by Bret Wong

I like them but people should be aware that they are not designed to be used many hours a day throughout the summer or the engine will wear out. They don't have brushless DC or AC motors like in computer fans, hardware, or brushless AC fans like window fans. They have motors with contact armature brushes inside, like most cordless tools, vacuums, toy cars, and drones. If you used them most of the day, every day, for several months, their motors would wear out too. They are designed for occasional use when power is unavailable or inconvenient - like hiking, fishing, stuck in traffic without air conditioning, staying cool on the hottest days, or hot days during power outages. If you plan to use it as your essential daily personal fan all summer long, buy another one when it wears out. It doesn't cost much to sell, so you might want to stock up on some spares if AC power isn't available, and that's your only option. If an AC power source is available, use AC-powered fans with a brushless motor to get the power needed for continuous, long-term use. Or get more sophisticated and much more expensive battery powered fans that use computer fans with brushless motors if power isn't available and you need to run the fan for several hours a day. They are excellent for hiking. At my age and condition, the heat can kill me, so I also like them to stay cool during a power outage. I keep one on my desk every now and then to cool me down, but not all day and not every day. With such a small size, low battery consumption and low price, they don't blow much. They provide a light, gentle breeze when placed nearby. This is a personal fan, but a few people sitting next to it will feel it. This is not a window fan. It won't cool an entire room, tent or apartment by placing it in a window, but if you don't have power it's better than nothing. If you want something more powerful, it costs more, and if it's battery powered, it uses more batteries faster. More wind requires more power/batteries. I tested their run time by placing AA size Tenergy rechargeable batteries in the "D" cell adapter case and using them in the fan. It ran on 2 AA (not D) batteries. It worked for 8 hours before I noticed the fan started to slow down. By 10 o'clock it had decelerated to the same speed as if it were at a low level with fresh batteries. By 11 o'clock, although it was still spinning, the breeze had stopped blowing from it. Type D batteries have about three times more power and run time than AA batteries. This gives you a very long runtime. My window air conditioner never circulates enough cool air into the bathroom. It's always very hot there. I don't want to open my bathroom window to let in the hot, humid swamp air. I put this fan in the bathroom door and I can feel a gentle breeze from the toilet 5 feet away. I realized that they do not blow. hard but very long. So I bought 3 to have enough cooling when camping or during power outages and as a spare if I wasted one (I use one on my desk sometimes because it takes up little space and is so portable). Use it for its intended purpose! It is not suitable for continuous use all day, every day, all summer long. This is a personal ventilator for casual or emergency use. I would probably give it 5 stars if they warned people not to use it daily all the time. I knew what I was getting, but others might not.