LightHouse Silver Diamond Mylar Reflective Sheeting Film Roll Hydroponics Grow 2 To 100M (1.2 Meter 2) High quality British Made Reflective sheeting which will maximise the use of light in your growroom. walls and ceilings! LightHouse Silver Diamond White is a silver light proof diffusion foil, white and silver poly that works in a similar way to a horticultural lighting reflector, spreading light more evenly and eliminating hot spots. sheet has smaller diamonds than a lot of the competition to give greater light diffusion.