Solar energy reaching your Tesla arrives as visible light, ultraviolet and infrared, and infrared is the invisible part most people associate with the feeling of heat inside a parked car. Kepler's nano-ceramic films are engineered to address solar heat across that spectrum while keeping the glass optically clear, which is why a lighter shade can still be a serious performance film. Because visible light transmission and solar heat performance are measured separately, the sensible way to judge an option is to look at both figures for the exact film and shade, rather than assuming the darkest choice is always the most effective. Your installer can talk you through how each shade in the range compares for your vehicle.