Quali-Pro® 82004438 25 lb Bifenthrin L/P Insecticide Granules. Bifen L/P is a 0.2% Bifenthrin sand based insecticide granule used for killing listed pests. Bifen L/P can be used to treat not only residential, but institutional, public, commercial and industrial buildings, parks, recreational areas and athletic fields. Once Bifen L/P is in the soil, it not only works as a killing method, but also as a prevention method.