1.PMMA(optical acrylic) materials 2.high light transmittance 3.good after-service specification:Product: BHPA880- ... of dollars. the range of application:It is suitable for PROJECTOR,PROJECTOR,EPIDIASCOPE and ,also suitable for Solar energy collector system, start ... sunlight, hot water heater, solar furnace, stage light,LCD projector,AV projector,HOME cinema magnifier and so on...over 10 year's ...