AiM L VetCaps offer proven effective control of horn flies and biting and sucking lice on beef cattle greater than 600 lbs.The AiM L (Advanced Insecticide Management with Lambda cyhalothrin and piperonyl butoxide) VetCaps System is made up of two components: AiM-L VetCaps and a VetGun . Provides a first-of-its-kind, convenient, stress-free, whole-herd horn fly control option that saves you time and helps reduce your labor costs. AiM-L VetCaps provides precise dosing with the pull of a trigger.