Non-toxic and environmentally friendly: made of high quality resin and plastic, durable, non-polluting, harmless to your fish, safe < p>The chest sinks to the bottom of the water , and the "iron chain" attached to the diver's chest is suspended in the water. With oxygenation, the diver floats and swings in the water, becoming more lively and active Frogman Height: 9 cm, length, width and height of the treasure chest: 5.5/4/5 cm, chain length: 10 cm.The treasure chest is sunk in the water, and the frogman is connected to the treasure chest by an "iron chain" and suspended in the water. With oxygenation, the frogman floats and swings in the water, as if trying to explore the treasure chest. , which is very cute and interesting. Adds lots of color to the aquarium.The pneumatic aquarium decorations can be connected using an air pump (not included). The decorations swing with oxygen, creating a vivid effect and increasing oxygenation.This product needs to be connected to an air pump (air pump not included) to produce a bubbling effect underwater. It can float up and down with the accumulation of bubbles in the water. It is beautiful and easy to install. Note: The data are all manually measured, please allow 1-3cm error, due to the difference in light and display, there will be a certain difference in color, the actual item received shall prevail.