1.Frame Thickness: 1.2mm; Frame: 88mm width.2.Bottom sliding designs with ladder type for more smooth drainage.3.This series can be made of Three track with gauze (External).4.The sash connect by a tap and to improve the are-tightness and water-tightness,the bottom sash have a leather strip.5.Glass slot: 20.5mm, could install 5mm+6A+5mm tempered glass.6.The series can be splicing window and bay window.