Wefts are used to change the level of the ducts. The wefts are used to bypass beams, ledges, obstacles on the way of the system when laying the duct system. For D 100-315 A=40 mm, for D 355-800 A=60 mm, for D 900 and above A=100 mm. For D 100-355 t=0,55 mm, for D 400-800 t=0,7 mm, for D 900 and above t=1,0 mm. It is possible to produce wefts by special order of any design. *E - axis offset