This is Atlantic Water Garden's 1 1/2" Bio-Balls, 150 pcs.. We have a large selection of Filtration/FilterFall Replacement Parts and other water features from Atlantic Water Gardens.
Manufacturer's Description
Atlantic's BB1500 contains 150 extremely durable, lightweight Bio-Balls that are easy to clean and reduce channeling. Each ball is 1_" in diameter and has nearly 25 square inches of surface area for bacterial colonization.