Dr. T's DT332 Bat-A-Way Bat Repellent 4 Pounds 4 lbs. granular size with one application lasting up to 4 weeks Primary ingredient is naphthalene (99.95%) Indoor usage keeps bats, birds and squirrels out; outdoor usage prevents rabbits from disturbing planted items Contains the only EPA registered bat repellent Easy to apply, easy to store granular formula eliminates mess