These plastic rods emit a strong scent, which is designed to stop cats from fouling the surrounding area. They can be effective against other animals that mark their territory by a scent trail, including rats, mice, foxes, badgers and rabbits They come in a pack of 4, which gives cover to an area measuring 4 square meters (about 12 feet along a flower bed or shrubbery). They are unaffected by rain, and one set will last about 10-12 weeks. The strong citrus (lemon) smell is quite pleasant, but it overpowers the cat's ability to smell it's own urine trail, so it chooses another area instead. This product is highly effective when used along with one of our electronic cat repellers. Please note that we do not distribute this product to hardware shops or garden centres