Rodenticides (rat and mouse baits), molluscicides (slug and snail killers), bird repellents, insect repellents not classified as insecticides, and certain pheromone-based pest-management articles are the most frequent occupants of this residual heading. The common thread is that each makes a pest-control or plant-protection claim but does not fit neatly into the insecticide, fungicide, herbicide, or disinfectant headings.

Classification follows the product's primary or essential function as described on the EPA-registered label. If the label's primary claim is insecticidal (killing insects), the insecticide heading generally applies. If the primary claim is repellency without a killing action, the NES heading may be more appropriate. When a product makes equal claims, the GRI 'essential character' analysis and any applicable classification rulings should guide the decision — a licensed customs broker or binding ruling request from CBP can provide certainty.