1. Material This analog display wall clock made of high quality acrylic material with white letters and numbers, ideal for the classroom or the office^ 2. Special Design The black clock face is designed to look like a blackboard, with each math equation looking like white chalk. Instead of traditional numbers, this wall clock has a different equation for each delimitation.^ 3. Funny Mathematical When the clock is ticking, the hands move around the dial, telling the time, which is indicated by a different math problem for each hour. This unique wall clock is a fun and challenging brain exercise.^ 4. Fashion Decoration A very fashionable decoration for the wall, especially for the classroom, office and study, and an ideal gift for your friends or their children^ 5. Application Ideal for the budding math student or anyone who wants something different in a watch. For classroom, study, living room, nanny bedroom, office.