The Optoma 100inch Manual Pull-Down Projector Screen with Speed Control is very simple to use. Pull down to the desired height, hold for 3 seconds and the screen will stay put. To retract, give one pull and the speed-reducing mechanism brings the Panoview projector screen into the case smoothly. This technology helps to reduce wear and tear and extend the screen's life. The design of this Optoma manual projector screen allows for easy installation to your ceiling or wall. Perfectly suited for venues such as classrooms, home theaters and meeting rooms, this wall mountable projector screen is a versatile and durable product.