There will be high requirement for windows and doors water-tightness if the building is located in a coastal city or a city with frequently raining all through the year.

MOSER window&door system combines water-blocking, catchment, drainage, anti-backflow, which guarantees the whole windows or doors waterproof performance.

For high quality German sealing rubbers improve the waterproof performance:
Waterproof rubbers block most of rainwater.
Water collecion cavity can accommodate the rain that has seeped in.
Water and wind proof covers not only guarantees water discharging smoothly but also can efficiently block the water backflow unter strong wind.

Moser windows water-blocking and drainage system sketch: