Check the listing for details. 4" x 14" 200 Micron Polyester Filter Sock w/ 4" Ring - Generic. Condition: New. Listed at 6.75 USD. Filter socks are used as a effective first stage of an aquariums filtration process and should be placed so that water coming from the tank filters into the filter sock first removing uneaten food, detritus, organic waste, dust and other small particulates from aquarium water. This dramatically improve water quality and reduce maintenance on pumps, reduced sump cleaning and less impact on the biological filtration by removing the excessive waste that would otherwise break down in the system. The routine use and rotation of filter socks will help reduce ammonia and nitrate producing organic waste from accumulating. Simple Method of Mechanically Filtering an Aquarium Great for Filtering Fine Particles Like Dust, Excess Food, Detritus, Organic Waste & Silt From Entering Your Sump Helps Keep the Sump Clean Quality Stitched Regular Use will Result in Crystal Clear Water Prevents Large Objects like Sand, Crabs & Snails from Damaging Expensive Pump Motors Micron Rating: 200 Approximate Size: 4.12" x 14” Type: Plastic Ring It is suggested to pre wash filter socks prior to placing on your aquarium. Listing and template services provided by inkFrog