Topcoat means the final coating system applied to provide the final color and/or a protective finish. The topcoat may be a monocoat color or basecoat/clearcoat system. In-line repair and two-tone are part of topcoat.
40 CFR § 63.3176
Terms used in this subpart are defined in the CAA, in the General Provisions of this part, and in this section as follows: