According to the birds > Against pigeons

Does not apply to the category Disinfection stands.

In addition to standard spikes barriers, spring or roof ridge barriers are also found in this category. Spring and spike barriers are mainly used for windowsills, which prevent pigeons from landing and thereby polluting them. Roof ridge barriers are intended for use on the ridge of roofs, where they effectively prevent the settlement of pigeons. The gutter type of barrier prevents birds from landing on the gutter area.