Zevo Indoor Flying Insect Trap Cartridge Refills are specifically designed to attract, trap and kill flying insects. These cartridge refills are compatible with the Zevo Flying Insect Trap (device not included - cartridges only). Specialized trap attracts household pests using a unique combination of blue light and UV light to trap them on an easy-to-change cartridge. Trap cartridges are effective against house flies, fruit flies, gnats and more. Check your cartridge regularly by pulling up on the tab, and replace the cartridge when it's full. For best results, place traps in areas you normally see flying insects while avoiding competing like sources, like windows. Use throughout your home in kitchens, bathrooms, garages, living spaces and more.