Used to reflect misguided light back onto your plants.
Mylar is a reflective wall covering used in greenhouses and grow rooms to direct unused light back to the growing space. Mylar is an inexpensive way to boost the efficiency of costly grow light systems.
What would be "lost" light, now is utilized for maximum efficiency. Attach to any surface for ultimate light uniformity. Get creative: mount to walls, poles, pots. Highly reflective. Use either side. Double the thickness of any other type on the market.