... 2) Foldable, easy to handle 3) Double lamp changer overhead projector with fresnel lens Features:1,Full function, ... and saves storage room7,Osram halogen lamp assure 50 hours lamp life8,Double currents shut off assure ... lamp changer assure continues presentation during lamp failure11,Overheating protection assure automatic stop at high temperatureSpecifications: Fresnel lens for OHP projector ...