All of the Brabantia bin liners are made from the same material, High-density polyethylene, this reduces the risk of rips and tears while using the liner. Each liner can be fastened by the colourful pull ties along the circumference of the liner. The size of the liner can be determined by the letter on the package but also the colour of the pull ties. If you are unsure of the size please feel free to call us and we can help determine it for you.