REHAU System 4500 windows and doors use compression-seal technology and multi-point locking hardware, and have a glazing capacity of up to 1 3/8-inch. The system has a simulated U-value down to 0.17, an acoustical rating up to STC 43/OITC 34, a structural NAFS rating up to AW-PG100 and an impact rating up to DP65. The system is available in tilt-turn, awning, hopper and fixed windows, as well as matching doors.