Review on 🐠 AquaticHI 4 Pack 200 Micron Felt Filter Socks, 4x10.5 Inches, Freshwater/Saltwater Aquariums, Ponds, Sumps/Overflows by Jhun Skaggs

When I bought them I expected them to be polyester felt. I don't know what they're made of, but you can't feel them. The material is very dense and plastic. From the outside it almost looks like wax. Maybe it's recycled milk jugs or something. I do not know. It's very difficult to turn them inside out to wash, so I'm not worried anymore. I think they're doing their job (pre-filtering the salty water in my tank's sump) so can't really complain. I just prefer real filtered felt socks.