Trimlite white internal grids come in two styles: Traditional and Prairie. Available with a our Cardinal Glass, one lite glass options. The insulating value of Cardinal's patented coating is nearly double that of an ordinary insulated glass unit. In winter, reflects heat back into the room. In summer, it rejects the sun's heat and damaging UV rays. The coating is virtually invisible to the eye yet blocks 84% of the sun's harmful ultraviolet rays. In fact, is the clearest, highest performing glass you can buy.