Telescopic posts permit a simple adaptation to difficult topographies in the avalanche starting zone. Preassembled main structures of 4 m width each can be flown by helicopter directly to the building site. The execution of the upslope anchor head and of the connecting brackets at the support facilitate deposition placement of the structure by the helicopter. The support engages in a v-shaped cutout and is secured to the anchor head by means of a socket pin. The post is placed on the preinstalled ground plate and is also secured by a pin.