I recommend Yongduo sound-proof doors and windows with three-layer composite sound-proof window: thickness: 16MM Overall: Three-layer vacuum glass plastic steel frame sealing strip Installation sound-proof capacity: about 40 decibels Price: 1380 yuan Heat transfer coefficient per square (calculated by square): less than 3 Advantages: 1. Save indoor space and make your usable area larger /2. It won't affect when you open the window. 3. Change the direction of air circulation and soften the wind direction; 4. It can also be ventilated in rainy days to effectively prevent rainwater from splashing into the room; 5. Increase the locking point to improve the sealing performance of the window sash; 6. Improve the release function so that others can't climb into the room from the outside when opening the window; 7. Improve the safety of doors and windows Nine advantages of sound-proof doors and windows: 1 isolate noise, effectively reduce noise by more than 75%-90%, and reduce noise by 44-53 decibels, up to 60 decibels. 2 environmental protection and energy saving, effectively saving 40-60% of electricity expenses. Special materials can effectively block 99% ultraviolet rays, reduce the risk of skin cancer, and effectively prevent leg color and furniture deterioration caused by ultraviolet rays. Windproof, waterproof and dustproof, even if water seeps into your first window, the top secret of Yongduo soundproof doors and windows is enough to make you sit back and relax. 5 strong confidentiality, good top secret and sound-proof doors and windows can protect your personal and family privacy very well. Eliminate condensation fog and frost fog blocking your sight. 7. Flexible opening, firmness and durability, doubling the service life of the original window, safe and reliable, and quick ventilation. The style is beautiful and generous, and the structure and color basically overlap with the original window, which does not hinder the line of sight; Easy to assemble, disassemble and clean. Adopt the latest nested construction technology in Germany, and the installation is fast. After installing Yongduo soundproof doors and windows, your existing indoor noise can reach or exceed the quietest environmental standard in China-Class 0 standard! 10 is installed quickly. The installation of this soundproof window can avoid civil works and the original window does not need to be demolished. A single soundproof window can be installed on the same day.