This 18" hanging wall mounted galileo thermometer w/ brass hook is a functional decorative item that is suitable for virtually any room or office. It's combination of color, function and artful design make for a fascinating and educational conversation piece for family and friends. Just look at the lowest floating sphere in the upper part of the cylinder to tell the temperature. This galileo thermometer is calculated in Fahrenheit. The range of the spheres is 62-86 degrees. There are seven multi-colored spheres in this thermometer. The spheres are made of glass. The thermometer is made by a German company that has production facilities worldwide. The temperature tags on the spheres are 24-karat gold plated stainless steel.