We Founded in 1992, Rilang Doors and Windows is the earliest leader in slim retro aluminum alloy doors and windows in China. With 15 years of rich experience in the repair of doors and windows in modern historical protected buildings, it is the only member unit of the China Cultural Relics Protection Technology Association - Modern Building Protection Committee in the industry. It is a long-term strategic partner of Swiss OTTOSTUMM steel door and window system in China, and also owns its own brand APPLETREE. The products developed and produced have received 16 domestic patent approvals. We are committed to becoming a world-class steel and copper door and window enterprise,We have been working hard to create buildings that will amaze the world!