1.profile: UPVC good profile with five-cavity & three-sealing. which can greatly improve window's heat-preservation, sound-insulation and energy-saving effects. 2.two operations: inward top hung and inward side hung. Practical and secure, at the same time good ventilated, an apotheosis of high-grade configuration. 3.hardware: whole set of special hardware for tilt and turn operation. Reasonable design, perfect function and exquisite material guarantee good air-tightness, water-proof and burglary-resistance of windows. 4.glass: triple glazing (5mm+9A+5mm+12A+5mm), intensifying windows' functions .