Without paint; unpainted, or whose paint has worn off.(adjective)
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Use "paintless" in a sentence
"The shack stood alone, dusty windows lining its paintless exterior."
"We put paintless dent repair to the test with four cars with dings, using some nationwide franchises as well as independent operations."
"There are a number of services that offer paintless dent repair, which involves using specialized metal rods to push out small dents from the inside."