I welcome you to come to our shop. Our products are 100% guaranteed. If you have any questions or dissatisfaction, please contact us.Size:3pcsMade of clear plastic, materials. It is hollow sphere, durable and convenient to use. Thread structure, easy to install and remove. No cumbersome DIY process. Transparent material, it is excellent Compatible with landscaping. Can grow aquatic plant and able to hold filter material. Also can be used Compatible with purifying water quality, It is suitable Compatible with shrimp cylinder. Can use as plant cultivation platform or filling filter Compatible with water purification. It is vividly and cute shape design, add lively and natural life to your fish tank. This moss holder is submerged style, please pay attention to this. The aquatic plant is not included here.Please allow 0.5 inch error due to manual measurement, please make sure you do not mind before you bid. How to use:1.Turn the filter counterclockwise and open it.2.Put the aquatic plant into the holder evenly.3.Turn the filter clockwise to close it.