Features: Biochemical Blanket or Bag filter provides biological filtration to the aquarium, helps to stable water quality. Increase the oxygen solubility. Working noiselessly, very durable, can be used for years. Good permeability, easy to clean. Perfect filters accessories for your tank and aquarium. Speicificaitons: Product name: Aquarium Blanket Filter Material: Polyester Color: White (Show as picture) Size: Blanket: 6.89x5.51in/17.5x14cm 11.81x5.31in/30x13.5cm 19.69x5.51in/50x14cm 5.12x39.37in/13x100cm 7.87x11.81in/20x30cm 11.81x11.81in/30x30cm 15.75x11.81in/40x30cm 21.65x11.81in/55x30cm 25.59x11.81in/65x30cm. Package Included: 1Pc Aquarium Blanket Reminder: 1. Soak the blanket or bag in the boiling water for 5 minutes before use, by doing this will help nitrifying bateria colonise easier. 2. Use tap water to rinse clean the blanket with fluff down; clean the bag by fixing it on the water tap. 3. Place the blanket in the wet and dry separation box with fluff up. Notes: Please allow 1-3cm differs due to manual measurement. Due to the different display and different light, the picture maybe a little different with the actual color of the item. Thanks for your understanding.