Release Films are typically placed directly in contact with the laminate. They separate the laminate from breather/bleeder fabrics, which have no release characteristics, while the thin plastic release film has been treated so it won't bond to the laminate. There are many types of release films available and selection will depend on such things as the cure temperature, pressure, complexity of component and resin system involved. Release films can be perforated or non perforated depending on whether or not resin bleed is necessary. Perforations enable trapped air, volatiles or excess resin, which may compromise the physical properties of the laminate, to be removed. Various perforation patterns are available with P3 being a standard medium bleed perforation and P31 a high bleed infusion perforation.