AirDrain Synthetic Turf Sportsfield Drainage Doubles as a Drainage Layer and Shock Pad.Whether installed on an aggregate base, concrete or asphalt the AirDrain drainage grid helps provide you with a consistent GMAX across the entire field. All but eliminating infill migration and floating, standing water. There is a difference between real world drainage and manufacturers claims. AirDrain can't be beat by anyone's product period.Unlike traditional shock pads / e-layer the AirDrain is 1" high, has a 92% air void. This unmatched vertical and lateral drainage all but eliminates standing water even at a 0.25% slope.