Defender Bird Spikes Fixing Silicone Adhesive Glue for attaching Pigeon Deterrent Spikes Defender Bird Spike Fixing Silicone has been specially formulated for fixing anti-bird spikes Strong initial grab, sticks pigeon spikes to clean, dry porous and non-porous surfaces Defender Glue is corrosion free & withstands extreme temperatures with a 35 year life expectancy 10 oz tube covers up to 25 linear feet of anti-pigeon spikes and bird deterrents. Low modulus, neutral curing, high tack and high flexibility. It is not subject to TSCA Regulations. Our standard Defender Plastic Bird Spike is for light pigeon infestations on ledges up to 4 inches wide. This means an area where the pigeons come and go during the day, but are not trying to nest or roost overnight. For a heavier infestaion where pigeons are already established and are trying to nest, we would recommend the Defender Stainless Steel Bird Spike for ledges upto 4 inches.