These plastic rods emit a strong scent, which is designed to stop cats fouling the surrounding area. The sharp citrus smell is impregnated within the plastic during the moulding process, which means that, no matter what the weather, Pest-Stop Cat Repeller Rods keep working for at least 10 weeks. Each rod protects approx. 1 metre square. Unaffected by the weather, will last up to 10 weeks. Discreet design & colouring blends easily into flower borders. No harmful chemicals or pesticides. Easy to use in the garden or for house plants.