an instrument panel top cover with a seamless break - away air bag door made as a unitary composite from multiple layers of plastics by extruding a parison with inner and outer layers of different recyclable plastics having different physical characteristics but which are from the same plastics family . the parison is injected and expanded with low pressure gas and forming dies with door scoring tools are closed thereover . the plastics will resultantly conform to the shaping surfaces of the dies to form the composite while the perimeter of the air bag door is scored . a quantity of the plastic material interior of the door score lines is removed after the top cover is removed from the dies so that a seamless or hidden door is provided that can readily break open at the peripheral scores to augment air bag operation when the air bag is triggered .