They consist of large diameter telescopic steel pipes controlled by a crane mechanism. These pipes provide a large internal area for easy discharge of powder material and isolate it from the environment. Thanks to the flexible and telescopic structure of the filling bellows, it extends vertically to the point or area to be filled. The material coming from the discharge point flows through the wear cones with its own falling speed. The dust particles formed during discharge are kept by the dust collection system between the outer and inner bellows.