【Protect Shrimp & Fish】– The mesh of the filter cover is small, which can avoid sucking small shrimps and fishes.Small: inner diameter: 12mm, suitable for waterfall filter, Large: inner diameter: 16mm, suitable for connecting 17mm outer diameter hose. 【Prevent Obstruction】– Can prevent large debris from being sucked into and blocking the filter system. 【Application】– Stainless steel micro-grid design, fine and smooth mesh, can prevent baby shrimp or fish from being sucked into the filter. 【High Quality】– Our aquarium filter net is made of high quality stainless steel material, sturdy and durable in use, compact and resistant to deformation. 【Easy to install】– Easy to install and convenient to use.It is recommended to clean the stains accumulated on the filter guard with a brush regularly.