Viewstar series of manual screen, using iron shell, built-in maintenance-free lubricating bearings and high load-bearing soft spring system, free flow strengths, to avoid tension caused by the screen surface deformation as well as sophisticated self-locking hand, can remain in the curtain Any location is suitable for all kinds of Video format player, Bo Zhu-specific or white plastic curtain and a high degree of high-gain, clear and beautiful picture, showing a perfect world, true color, suitable for conference rooms, classrooms, exhibition hall, and other places of use.