Size: Our diving gemstone toys have three sizes, five large diamonds (40 mm/1.57 in), two medium diamonds (30 mm/1.18 in), and three small diamonds (20 mm/0.78 in). The size of the box is 8.8 cm * 5.3 cm * 5.3 cm/3.46 in * 2.08 in * 2.08 in. Put these diamonds into the box, and children can go to the bottom of the swimming pool to open the box and take out the diving gem. PS: Please measure according to the dimensions provided by us when purchasing, and choose to purchase if it meets your own requirements. Reliable Material: Dive throw toy set is made of acrylic material, non-toxic and harmless, could be used for a long time, not easy to fade, suitable weight, could sink to the bottom of the water, children could use it with confidence.PS: Suitable for children, please use with the accompaniment of an adult. Do not throw diamonds in dangerous areas such as drainage ditches. Do not throw diamonds into areas with people while playing. Diverse game play: The sinking gem toy is perfect for swimming pools and pirate games, throwing diamonds into the pool allows kids to go and explore, find fun and enjoy swimming. You could also put gems in boxes and hunt for treasures with your friends.Come and discover other more interesting ways to play together. Wide Range of Applications: Swimming pool diamonds are fit for decoration in various places such as summer parties, pool parties, beach parties, birthday parties and diving toy school activities.And you could also give it as a gift for kids, boys, girls and swimmers.