This Material Specification defines the requirements of carbon fiber reinforced epoxy prepreg for repair, 120 °C (250 °F) Vacuum curing, Plain Weave Fabric, 193 g/m2 and a companion non-structural glass fiber fabric reinforced epoxy prepreg, 105 g/m2, qualified according to AMS3970/1 and AMS3970/2 for aerospace application. The prepreg system may include an epoxy film adhesive to be applied in a co-curing process with the prepreg for joint and sandwich bonding. The need for a film adhesive shall be established during screening tests. If included, the requirements to be met by the adhesive are also defined in this document.