Being semi automatic, lowering of these bollards is done by manual key unlocking on the bollard’s head, until it locks itself into a lowered position.
Manoeuvring the key anew releases the energy stored in the cylinder: the bollard is lifted back up and blocked by upper stops. A polyurethane peripheral gasket cushions the end stop, while ensuring sealing.
The in-ground casing acts internally as a guiding rail and externally as a casing. Surrounded by concrete at installation, this bollard is highly shock-resistant.