Safer Brand 51703 Diatomaceous Earth-Bed Bug Flea, Ant, Crawling Insect Killer 4 lb Diatomaceous earth-based powder is a highly effective ant killer; 4-pound resealable bag Kills insects by ingestion/dehydration within 48 hours indoors or outdoors Also for bed bug, cockroach, flea, earwig, silverfish, cricket, millipede and centipede control Insects cannot develop a resistance to it since there are no chemicals to build immunity from Formula contains 100% Diatomaceous Earth