Product Features: Polyethylene Construction: The Schluter-TROBA-PLUS waterproofing mat is constructed out of polyethylene, allowing it to withstand the rigors of years-long use. Allows for Free Water Flow: Schluter-TROBA's construction design allows water to flow freely from one side of the mat to the other to a designated water drainage point. This preserves flooring even in low-ground-level environments. Water Management: Durable subsurface drainage system for exterior applications. Permits water to drain off freely and reliably Continuous Drainage Layer: Creating a continuous drainage area above the waterproofing layer Generous Roll Coverage: 3'3" x 41' = 134.5 Ft (1 m x 12,5 m = 12,5 m) Low Profile Thickness: Thickness 5/16" Product Description: Schluter-TROBA-PLUS is a sub-surface drainage system used in horizontal waterproofing layers. It is constructed of pressure-stable polyethylene with closely positioned studs, enabling water to flow down a slope to a designated drainage exit. Its reliability and durability allow it to provide steadfast waterproofing over a span of years.