Double your growing room with this Hydrofarm Black And White Poly Film. This heavy duty, waterproof film is a great alternative to metalized film. Simply unroll the black and white film and custom fit it to your garden. Use the white side for walls and floors and take advantage of its 90 percent reflectivity. Flip the film over to the black side when you want to block light and sunshine, it is completely light resistant.When you add this plastic poly film to your walls, there is no structural changes to be made and no expensive heating lights to be purchased. You can rely on this Hydrofarm Black And White Poly Film to provide more grow room and attract and block light for your plants.