Scupper is made of 26 Gauge Galvanized Steel, Center, Left or Right flange options, 10" or 12" Stem length. Hot Solder as Option. Scuppers, or Roof Outlets, provide a pathway for water to flow through parapet walls or any other raised edge around a flat roof. Primary roof scuppers normally channel water off the roof into a conductor box (leader head) that connects to a downspout or gutter. Some Scuppers have a simple spout that pours water down the side of the building, while others are connected to downspouts that send the water directly to the ground level. For architectural, residential, and commercial roofing. ASTM A-653, ASTM A-792