Grey Plastic 70mm Soffit Air Vents. Pack of 10. Suitable for new or existing soffits. Push in soffit vents for roof and eave ventilation. Meets building regulations. Made in durable polypropylene. Provides a free airflow of 2150mm² per unit. Dimensions: Vent size: 80mm. Drill hole size: 67mm. Vent depth: 15mm. Circular soffit vents can be slotted into the soffit board prior to installation for new build situations or just as easily retro-fitted into existing soffits. Standard fixing for this product is a simple push twist action into a 67mm hole drilled in the soffit board. The vent features evenly spaced slots small enough to prohibit large insects gaining access but wide enough not to be blocked by debris, paint or water droplets. Product Specification: 2150mm² per soffit vent. To achieve 10,000mm²/m of free airflow the G700 should be fitted at 200mm centres. To achieve 25,000mm²/m of free airflow the G700 should be fitted at 86mm staggered centres. Push fit into 67mm diameter hole in soffit board.