Galvanized steel Y-pieces 90° with d2=d3.
Connection pieces with airthightness class C to EN 12237.
The airthightness class is also determined by the mounting on the construction site.
Explanation :
BSG90 = Type of Y-piece
250 = Diameter of all duct connections
Explanation :
BSG90 : Type of Y-piece
250/2x200 : D1=250 mm en d2=d3=200 mm