Now you can help reduce the huge number of birds killed each year flying into windows. Window Alert is a static-cling decal that's easily applied to windows at home, at the office, on greenhouses, conservatories or anywhere that glass may creat an invisible (and fatal) obstacle. The decals contain a component which reflects ultraviolet sunlight
- undetectable to humans, it glows brightly for birds to spell out danger ahead! Pack of 4 decals, each about 10.2cm (4") diameter. 1 decal is sufficient per m-square.