【Quality Material】- The math equations clock measures 12 inch. Physics wall clock is made of thick acrylic, sturdy and lightweight 【Battery Powered】- This math unit circle clock runs on 1 AA battery (not included). Geeky calculus wall clock keep good time 【Silent Mechanism】- The math engineering wall clock comes with a quiet and non-ticking mechanism to ensure a quiet environment 【Easy to Hang】- Our math decor wall clock has recess on the back for hanging on the wall, comes with hook 【Ideal Gift】- Our math nerdy analog clock with mathematical expressions gifts for math teachers, math lovers, engineer student. Math teacher trigonometry themed gifts for men. This math themed clocks for classroom, school class, office, bedroom, living room, kitchen, bathroom and so on