Black and White Poly 6 mil (per foot)
Price: $1.60 CAD
White reflective poly, also known as 'panda film', with light proof black backing sold by the foot.
The thickness is 6 mil which makes this product very strong and durable.
The Poly is sold by the linear foot but opens up to 10 feet wide. So every foot you buy is actually 10 square feet.