SPT – Thermal Double Wall Duct
Outer Shell: Solid Galvanized Stell.
Inner Shell: Solid Galvanized Stell.
SPA – Acoustical Double Wall Duct
Outer Shell: Solid Galvanized Stell.
Inner Shell: Perforated Galvanized Stell.
Inner Shell Diameter mm d1
Outer Shell Diameter mm d10=d1+2l
Insulation 25mm Or 50mm
Insulation Density: 24 Kg/m3 As Standard
