Use doors and Windows K value to choose good doors and Windows!
Doors and Windows are an important part of interior decoration, it bears a series of important parts such as ventilation, lighting, safety, heat insulation and so on, basically it can be said that it is an indispensable part. Then, with the national team's energy-saving and environmental protection requirements becoming higher and higher, the doors and Windows also extend a constant value, which is what the expert calls the K value