.com.hk is a country-specific Internet Domain (ccTLD) from Hong Kong.
Hong Kong is one of two special administrative regions of the People's Republic of China; the other is Macau. Situated on China's south coast and enclosed by the Pearl River Delta and South China Sea, it is renowned for its expansive skyline and deep natural harbour.
Within .com.hk the term .com is the abbreviation for "commercial".
Thus this domain is especially fitting for tradesmen and other commercial entities related to Hong Kong.