Product is steel or aluminum alloy shell, sturdy and durable.Can choose Eor D type support,more flexible.The 4:3 screen is more suitable for modern people's viewing habits,real clear picture.Portable design is easier to carry.This product is suitable for small conference rooms,classrooms,exhibition hall and other places.Humanized design is more convenient for the use of your daily life.Special curtain restores the ture color.Watching for a long time won't feel tired.