Features: 1) Utilizes advanced TRANSAC-BRIDGE technology, is environmentally friendly, and economizes energy use.2) Conquers the common problems in aluminum alloy shapes for heat insulation and sound insulation. It has the following characteristics: a) High intensity b) High-grade airproofing property c) High-grade waterproofing property3) Not only luxuriously sculptured, but also has advanced technology as its advantage4) Its entad-opening and entad-closed design is nationally patented5) Energy efficient6) It is beneficial to achieving individuality in decorating your house by allowing free assembly of windows and doors, with various series available in a large variety of colors