Maunco Thick-Wall Poly Bags are made from 100% ECOLOGO Certified, recycled resin, which makes them an environmentally beneficial alternative to other brands of poly bags. The boxes that hold our bags are also made from recycled material. Thick-Wall Poly Bags are rated by the minimum weight that they will carry ... a “40lb bag" will carry at least 40 pounds of garbage or recycling, a "70lb bag" will carry at least 70 pounds, a "90lb bag" will carry at least 90 pounds, and our "150lb bag" will carry a whopping 150 pounds.