Anti-sanding timer: - The high-quality material protective cover makes the hourglass stopwatch not easy to break, and it is very durable and beautiful. Do not break under normal use, but do not fall from a height. Counting time: - 3 minutes with a time difference of 10%. Filled with exquisite sea sand, the sand goes smoothly and does not get stuck. Material: - Durable PVC, high borosilicate glass and sand. Each size: 3*9cm. 2 identical hourglasses are packed in a package. Application: - Great for kids tooth brushing timer, home, classroom, game, exercise time. Can teach children the meaning of time with the visual angle, used as a wonderful decoration for home and office, great as a gift for children and friends. Notice: - This is an hourglass designed for games. It is not a precision stopwatch, so there is a time deviation.