In China, doors and windows are of medium grade. According to the news released by official website of Longtu Doors and Windows, Longtu Doors and Windows have a market share of 22. 15% and a popularity of 35%, ranking 18. China's top ten doors and windows brands are not as powerful as Longtu doors and windows. Among all kinds of doors and windows in China, Longtu doors and windows are not in the high-end ranking, but they are ranked in 18, which is considered as medium.