... borosiliate glass Refractive index 1.474 Working Temperature -50-550 degree Light Transmittance 95% Photometrical curve round light shape Diameter ... 78mm View degree 60 degree Lens price 2.98 ~ 3.63 USD/Complete set ... Led high /low bay light,factory,warehouse,mine,workshop,big toll station,gas station,stadium,exhibition,wharf and other long ...