A selective insecticide that works as a growth regulator rather than a nerve poison, blocking the formation of chitin so that larvae cannot complete their molt and die before reaching adulthood. Because it targets a process unique to insects and related arthropods, it is considered relatively gentle on mammals, birds, and many beneficial organisms, and environmental agencies classify it as only slightly toxic. Growers apply it to fruit and vegetable crops to control leaf-eating caterpillars and other larvae, and veterinarians use it as an ectoparasiticide on sheep. As with all crop chemicals, maximum residue limits, pre-harvest intervals, and residue monitoring programs govern its use, ensuring that treated produce reaching consumers carries residues well within established safety margins.