Agrilabs Aim-L VetCapsAiM L Vet Caps 30ctVet Gun Capsules AiM L VetCaps are scientifically developed gelatin capsules designed to be used exclusively with the VetGun. Each 10 mL capsule contains lambda cyhalothrin (a pyrethroid), an Environmental Protection Agency registered topical insecticide proven effective for control of horn flies, and lice on beef cattle. As a topical insecticide, users can expect a quick knock down of horn fly and lice populations as they come in