Feature: 1. The use of sand and stone material can make your aquarium fish tank outgas better. 2. It can be used as a decorative object to add a landscape to your fish tank. 3. This product can be cleaned and can be used repeatedly after cleaning. 4. There are two sizes, so you have more choices to meet your different needs. 5. Made of environmentally friendly materials, is durable and non‑toxic, and can be used in various aquarium. Specification: Condition:100% Brand New Item Type: Aquarium Sand BarMaterial: PVC, SandstoneSmall Size Length: Approx. 11.7cm/4.6in Large Size Length: Approx. 21.7cm/8.5in Instructions for Use: 1: Please soak this product in water for 15 minutes before use 2: Long-term use, if dirt clogged, air bubbles reduced, it can be taken out and washed repeatedly 3: It can be used with 2W and above air pumps (the larger the wattage of the air pump, the better the air output!) Product Function: Used in conjunction with air pump and air tube pump, more bubbles. Package List: 5 x Aquarium Sand Bar