Crystal trivision display 1.Full set digital control equipment 2.Maintenance free 3. ... equipment2.Maintenance free3.CE,ISO900,National invention Patents Crystal trivision display ,trivision billboard The specification:Scrollspeed : 0.15-0.24m/sScroll ... suit for the mall ,park,airport,bus station ,subway station,supermarket,restaurant,bank,exhibition, special size for indoor and outdoor.