These are PP film rolls coated with non drying adhesive on both the sides which trap insects/pests when in flight. When you have an insect population in a large area that you need to monitor and trap, this sticky roll is the answer for you. If you are dealing with an invasion of Western Flower Thrips, you are advised to use the Blue Sticky Roll. Blue Sticky Roles have been tested, on different crops and in various conditions. Trials showed that these rolls can reduce adult thrips numbers. It is very useful for attracting insects from long distances.