Search query: heat recovery ventilator

Product: iPower 4 Inch 150 CFM Inline Fan with Variable Speed Controller Air Carbon Filter 8 Feet Ducting Combo for Grow Tent Ventilation, Silver 4 inch 150 CFM duct inline fan blower: made with quality components for quiet operation. Composite fan blades and center hub which reduces noise and vibration.
4 inch 1050+ IAV Australia charcoal filter: one of the world's most absorbent carbon available; dimensions: 4" flange ducting x 12" length; reversible flange; free pre-filter included.
Fan speed controller: variable speed, OFF, HIGH, MED, LOW. To avoid the risk of burning out the fan motor, controller does NOT adjust below 50%.
4 inch 8 feet uninsulated aluminum ducting + 2 stainless clamps: flame-retardant coating and corrosion-resistant wire helix; temperature endurance range from 0 ~ 185°F. (-18℃ ~ 85℃). Free pair of 4 inch metal clamps made from stainless steel.
Multi-Functional: this ventilation combo removes heat and eliminate the undesirable ill-smelling odors in the grow tent to solves air delivery problems without major system rework or expense. Wide applications: kitchens, greenhouses, grow rooms, etc. iPower Silver

Product: Fantech VHR 150R Heat Recovery Ventilator(HRV), 3 Speed Unit Airflow up to 159 cfm @ 0.4" PS serves 2 to 5 bedroom homes
Compact top port design
Internal recirculation defrost
6" oval collars
Integrated airflow measurement system allows for rapid and accurate reading of airflow during installation Fantech