Diatomaceous earth-based powder is a highly effective ant killer; 4-pound resealable bagKills insects by ingestion/dehydration within 48 hours indoors or outdoorsAlso for bed bug, cockroach, flea, earwig, silverfish, cricket, millipede and centipede controlInsects cannot develop an immunity to this product unlike traditional insect killersFormula contains 100% Diatomaceous Earth