... 3) high temperature resistance 4)clear solar concentrator glass lens(GT-D22-10-1)1)material: optical glass(borosilicate),K9,BK7 ... ,B2702) light transmittance: 95%( coated lens can up to 97%) 3) Size: 4) shape ... , projector light,optical instrument,astronomical instrument. solar concentrator glass lens(GT-D22-10-1)