The Vent-Axia Lo-Carbon Tempra P 100mm 4" Heat Recovery Fan with Pullcord (443312) offers an efficient solution for properties requiring effective ventilation and energy conservation. It fits easily into a 100mm diameter hole, making it ideal for refurbishments, and provides impressive heat recovery of up to 78%. The Tempra P operates efficiently with a wall depth of 320mm, running continuously at 6 l/s or 9 l/s, and can boost to 15 l/s for peak performance. Its manual summer setting allows for extract-only operation, ensuring comfortable indoor temperatures in warmer months.