Glueboard fly killers attract flies by using UV lights to mimic natural light. Flies are then attracted to the units, causing them to become stuck on the sticky pads used. Due to the build-up of flies, sticky replacement pads are often purchased alongside. Sticky fly killing machines are ideal for areas concerned about hygiene, such as kitchens and food preparation environments. Depending on your circumstances, you may require a range of electric fly killers. Furthermore, it is recommended that the fly killer bulbs be replaced every 12 months.