Rips cardboard filters (also known as roach material) are a form of filter that do not restrict the draw or flavour of the cigarette and filter the smoke as it passes over the card. They filter a lot less than a fibrous filter but are better than nothing for those who want a fuller flavour. They also prevent tobacco bits getting into the mouth and yellow staining on the fingers.
The Rips Roach filters are the only filters with the perforations, which when folded before rolling make fins in the centre of the filter to make it firmer and putting more surface area for the smoke to pass over.