Because I want to have fresh air at night necessarily, but from a full gestelltem on tilt window at night, the morning woke up with sore throats, I ordered this tilt control on the recommendation. Installation is super easy. It can be mounted on both sides, if you set about the control pin. On the very first stage, sufficient fresh air comes into the room, but not so much that it hurts the neck or one gets frostbite. :)