Precor 2000 Plus Premise Spray contains Permethrin and Phenothrin to kill adult fleas fast. It also contains Precor IGR to prevent reinfestation for up to seven months. Precor IGR penetrates deep into the base of carpet and upholstery fibers, where pre-adult fleas live. Precor IGR targets fleas in the egg and larval stages of development, preventing them from producing new infestations of breeding, biting adults.