1 U valve 1.4w/m2k
2 aluminum-clap wood profile
3 double toughtened galss with argon
4.rotate 160 degree

easy to build in for roof inclinations from 15 °to 90 ° easily operated handles window sash can freely stop at any angle,ventilation and light transimission guaranteed rotation opening160 °,convenient for clean the outer glass thickened aluminium alloy flashing of better durability and acid-resistance