There are 2 opening window clips which should be attached to each end of the spike. These clips have 2 indents on either side, which are for screwing the clips to the bottom of the actual window frame. This is the recommended method as, once correctly installed, the spikess are then ready to keep pigeons off window sills.
Another method is to silicone the clips to the bottom of the window frame. This involves taping the opening window spike into position and supporting the underneath of the pigeon spike to keep it level whilst the adhesive silicone goes off – this should take a maximum of 24 hours.
NOTE: Not every window is the same size, so the Spikes may need to be resized to fit a particular window. The base of the bird spike itself has snappable grooves along it, so it can be made smaller to finish a run at the end of an opening window ledge or window sill. Then place the clips at each end of this piece.
WARRANTY: The spikes and clips are produced from a high quality plastic that is UV stabilised. As the opening window spikes are likely to be in direct sunlight, the use of this tough plastic means they will not discolour or become brittle. With this in mind, they come with a 15-Year Warranty