Johnsons 4fleas dual action spot on for cats under 4kg is a rapid monthly spot on treatment to kill fleas on cats this treatment is formulated with avm gsl containing active ingredient imidacloprid to help effectively kill fleas on contact its dual action kills ea larvae not only on your pets body but also in the area around your pet including their bedding resting areas etc this treatment contains 2 pipettes unique features 1 treatment prevents further infestation for 3 to 4 weeks f