Advanced-generation pyrethroid (lambdacyhalothrin 10%) plus synergist (piperonyl butoxide 13%) provide increased insecticidal activity. Easily applied and stays in the ear for the life of the tag. Can be used in beef cattle of all ages including day-old calves. Two tags per head provide up to 5 months’ control of horn flies and up to 4 months’ control of face flies.