Carlos Koo is a Hong Kong based actor and model, as well as a metal engraver known for pioneering hand-engraving on objects like motorcycles and watches. He is a motorcycle enthusiast who became inspired to learn hand-engraving after seeing an engraved motorcycle in a magazine and has been practicing the craft for over 20 years, including studying under master engraver Dewa Saputra. His work emphasizes traditional, time-consuming techniques in contrast to modern laser engraving.