Age: 3 years and up Diameter: 16mm (5/8") Decorate your favorite aquarium that will delight your children when playing marbles. Aquarium decoration DIY your favorite pattern when you are time to enjoy a beautiful scenery and good mood. Material: Glass Color: Blue + Transparent Package Content: 20 x Glass Balls (Blue x 10, Transparent x 10) Package Content is more than 1, other products are not included here. Note: The color and size of the actual item may vary slightly from the color and size on the website due to lighting and display conditions. The margin of error for the measurement is 0.4 - 1.2 inches (1