STEM Flying Insect Light Trap Refills 6 Cartridges Total Chemical Free STEM Flying Insect Light Trap Refills provide an effective, chemical insecticide-free solution for managing household pests. Designed to attract and trap house flies, mosquitoes, gnats, and fruit flies, these dual-sided sticky cartridges are people and pet-friendly when used as directed. Each box contains two refill cartridges that are compatible with both STEM and Raid Essentials Light Trap devices. These blue refills offer a discreet yet powerful way to keep your living spaces clear of flying insects without harsh chemical odors.