100% brand new and high quality Feature A UNIQUE WAY TO TRACK THE HOURS Instead of Roman numerals or traditional numbers,this wall clock has a different equation at each demarcation PERFECTLY SIZED Clock measures 11-1/2 inches in diameter and is easy to spot from afar GO WITH EVERYTHING DESIGN Black and white color scheme makes the clock look like a chalkboard and will complement any color palette GREAT GIFT IDEA Give one of these wall clocks to a math teacher,engineer,mathematician or anyone who just loves numbers NO CORDS OR WIRES Clock runs on one AA battery (not included),Only insert Carbon batteries. Specifications: Item size: Diameter30.5cm/12in Acrylic thickness: 4mm Material: Wood Style: Novelty maths equation Powered by 1*AA battery(not included) Package1 pc clock Note: 1.The real color of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness 2.Please allow slight deviation for the measurement data