Each carton contains 10 vents. The proVent attic ventilation channel provides an unobstructed air channel through your insulation. Without proper attic ventilation, air cannot flow freely from the soffit to the exhaust vents. Poor air flow reduces insulation efficiencies and accelerates problems due to moisture. ProVent may be installed prior to the soffit panel without fear of blow-out. It is recommended that one proVent channel be installed per rafter or truss cavity. This product is ideal for premium construction and difficult applications such as re-insulation jobs.