Beaphar Calming Collar for cats effectively reduces problem behaviour arising from stressful situations in cats of all breeds and ages. Using Valerian and Lavender which are often used in human healthcare to manage stress. it leaves cats feeling calm, settled, relaxed and reduces problem behaviour. This can be especially important in a multi-cat (or pet) household as cats are particularly sensitive to other animals and changes in their environment. Once fitted, Valerian will be released immediately and the cat will begin to relax within approximately one hour and will be effective for up to 6 weeks. Size: 35cmHow to use it?Fasten the collar ensuring a comfortable fit so that two fingers can be inserted between the collar and neck. If fitted to a growing cat, remember to loosen the collar regularly. Cut off any excess collar and dispose of with the household rubbish. For the collar to stay effective, it is important it remains next to the skin. Other collars should not be worn at the same time, or the effect might be reduced. Do not open the sachet until you are ready to use the collar. If the collar gets wet, it will continue to be effective once it has dried. If you want to wash your cat with shampoo, it is best to remove the collar and replace when the cat is dry.