I saw this product in someone's youtube video and as soon as I saw how well it worked I knew I needed it! I have an air compressor in my workshop that is great for inflating tires and other things. However, air compressors are loud, mine is as loud as a lawnmower! And you have to take care of the maintenance, changing the oil in the compressor, emptying the dehumidification tank frequently, that's not exactly something a homeowner wants to bother with. The great thing about this device is that it is portable and it is only 5 inches long. , about 2.5 inches wide and weighs only a pound, making it easy to take with you. It is powered by a lithium battery that can be charged via USB. It has an LCD screen where you can see the current tire pressure and set the desired pressure that you want the device to inflate the tire to. You need to hold down the power button for a few seconds until it turns on. The same applies to switching off the device. Just hold for a few seconds until it turns off. This device comes with several accessories including a Presta valve adapter and a sports ball inflation adapter. Just slip the flexible hose over the device, nice and clean but not too tight. The female end of the hose connects to the tire valve stem. The tip actually rotates to make threading easier. Turn on the device then you can see the tire pressure, when the tire is flat nothing is shown at all. Use the +/- buttons to set the desired pressure according to your tire specification, then just quickly press the ON/OFF button. Another great feature of this device is that once it reaches the set pressure, it will automatically stop inflating! The accuracy of the inflation percentage is +/- 1%. So far I've tested it with bicycle tires as well as garden tractor and trailer tires. The time to inflate depends on the size of the tire and the pressure required. The part where the hose enters the device will become warm after inflation, this is normal due to pneumatic compression dynamics. In my opinion this unit works great, it's a bit noisy but a far cry from the volume of my air compressor. So far it hasn't missed a beat and works as advertised. IMHO this is the most convenient and easiest way to inflate tires. I would only recommend this for small tyres, at most small garden tractor and kart trailer tires and barrel wheel tyres. This is not intended for car and truck tires, use a 12v or 120v compressor for this. 5 out of 5 stars!