The Tilt Hydrometer is a must - have for homebrewers. Whether you're brewing in your garage or a small home brewery, it helps you keep tabs on your beer's fermentation process. It can accurately measure specific gravity within the 0.990 to 1.120 range (accurate +/- 0.002) and temperature with an accuracy of +/- 1 degree F. You can use it with most Bluetooth 4.0+ devices, including iPhones, iPads, Android smartphones, and tablets. Simply sanitize it, drop it into your fermenter, and use the Tilt App to get real - time data. Its battery lasts 12 - 24 months, so you don't have to worry about frequent replacements.