Avery Dennison UC900 Light Diffuser is a cast film that partially blocks transmitted light to even out hot spots in backlit and illuminated signage. It is offered in 30% and 60% diffusion grades for different light-control levels and diffuses output from LEDs and lamps in light boxes and channel letters. It uses a permanent acrylic adhesive on a liner. Recommended for backlit sign faces, light-box graphics, and channel letters.