Ø 150mm / 6'' Round Spigot Ensures a Secure and Efficient Connection to your Ventilation SystemDurable ABS Plastic Construction for Long-lasting Performance in Outdoor EnvironmentsCowled Design Prevents Rainwater and Wind from Entering the Ventilation SystemIntegrated Backdraught Shutter / Damper Flap Prevents Reverse Airflow and Minimizes Unpleasant Odors or DraughtsIdeal for Garden Sheds, Greenhouses, and other Outdoor Structures | Perfectly Suited for Use with Bathroom Extractor Fan, Tumble dryer, Cooker hood, Hydroponics, etc.