... .Chambers: 3, 4, 5, 6, 4.Thikness:2.5MM Plastic sliding windows/doors ; excellent quality;energy efficient&safety; acoustical insulation. 1 ... glass, laminated glass, argon gas gass, etc.3. Glass thickness: single, double, tripled 5mm, 6mm, 8mm; Space: 6, 9, 12, 16mm ...