glass yard sunroom made in China Our History Founded in 1992, Tangshan Joyfident Energy-saving Technology Co., Ltd. is an enterprise focusing on the R&D and manufacturing of energy-saving doors and windows Our Factory The company is located in Caofeidian, the pearl of Bohai Sea. The factory covers an area of 60,000 square meters, with a production workshop of 20,000 square meters. It is...