1.Independent research technology-beautiful appearance and reasonable structure
2.the capability of wind-resist:2500Pa-3500Pa
gas-dense index: 0.8m3/mh(under 10Pa)
water-dense index-lower track: 250Pa, under track with high side: 350Pa
3.single or double glazing windows（5+6A+5）, to exchange sash material and line
4.inside or outside window screen
5.the security design- window sash being not disassembled from outside
6.“Longding” Brand hardware or PVC fittings
7.to select narrow or wide tracks and to select single or double pulleys
8.thickness of forced stick:1.4mm. 1.1mm or 1.2mm for inside windows |
