Gutter guards are exactly what you think. They’re devices installed in or on your gutters to protect them against leaves, sticks, and other debris that can clog them, leading to damaging leaks, overflow, ice dams, sagging and other damage requiring costly repairs. Their success generally depends on the types of trees you have on your property and the proximity of those trees to your roof. If you have trees close to your house that shed small needles, for example, guards with larger holes probably wouldn’t work well for your gutters.