The Delta-MS dimpled membrane is impermeable to water and water vapor. The vacuum formed exclusive dimple pattern creates an air-gap between the membrane and the foundation wall. It is easily installed by unrolling the chocolate colored membrane against the foundation wall. It is made with recycled high-density polyethylene, encapsulated between two layers of special virgin HDPE. It has an excellent chemical resistance, resistant to root-penetration, rot-proof. Non-toxic, non-polluting. Service life expectancy of more than 25 years (at pH between 4 and 9, and temperature below 25°C). Do not expose to UV light for longer than 30 days.