Micron Filter Socks Instantly improve your water quality with our pre-rinsed 200 micron filter socks. These highly durable mechanical filters help trap uneaten food, free floating particulate matter, micro-bubbles, and even dust from your aquarium. Pre-molded with internal plastic handles for easy servicing and double stitched for maximum reliability, micron socks are truly the BEST upgrade to your filter/sump for polishing water. The result, a CLEANER & CLEARER aquarium! FEATURES: High Quality Double stitched Felt 200 Micron pore size Pre-rinsed for instant use Made in USA Internal Plastic Handles for convenience 4 x 12 Individually labeled with quick-tear UPC on exterior * Note: Please Rinse All Filter Socks in RO or RO/DI Water Before Use