THERMOFLO Black & White Poly

Thermoflo Black & White Poly is the strongest commercial grade 6mm (+/-) on the market. The white side reflects 90% of light back to your plants. The black side blocks all light penetration. This heavy duty waterproof poly comes individually bagged and boxed for customers' convenience.

White/Black plastic (also known as panda plastic or "poly")

"Poly" is useful if you are setting up a temporary grow room or don't want to damage the walls. Poly is easily cleaned.

The purpose of the black side is to not allow any light to pass through the plastic, which ensures your dark cycle remains dark. The white side is 75-90% reflective. Choose a 6 "mill" thickness of poly for maximum light blockage and durability.

Picking the right surface for your grow room walls

Choosing the right surface for the walls of your grow room is very important, as up to 40% of your total yield comes from the edge, and the right wall surface can increase the amount of light those plants receive by up to 30%! Artificial lighting diminishes exponentially with distance, so it is important to contain as much of this light as possible, and direct it accordingly. Reflective surfaces also help illuminate the lower portions of the garden, providing lower buds with light and heat energy.

For Best Results

To get the best results with your light and walls, it is important to get the walls as close as possible to your garden to ensure the least amount of light is wasted. As a caveat, the percentages provided are only useful as a general guideline, as they present the range of reflectivity of the particular surfaces. The high percentage presents the best possible circumstances for that material (for example a 99% reflectivity rating for mylar sheeting would be under ideal conditions - no creases, completely flat, no discoloration, etc).
The best way to determine how well your grow room walls reflect light would be to purchase a light meter. And measure your light directly; then take an opaque board. And hold it a few inches off one of your walls. With the light meter below the board in such a fashion that the light reflects off the wall. And onto the light meter. You can then compare the difference between the two and determine a percentage. From those numbers, the closer the two numbers are, the better your wall reflects light.
Also important to note is that radiant light energy refers to electromagnetic (EM) radiation. With a wavelength between 400-700 nanometers (nm) and radiant heat energy correlates to EM radiation with a wavelength between 800-2000nm.