Thank you for viewing! This is a calming collar for cats from the overseas brand "Sentry." This product is scientifically proven to release cat-appeasing pheromones, reducing stress-related inappropriate behaviors (inappropriate marking, excessive vocalization, scratching, etc.). It can be used in stressful situations such as when left alone, with new family members, guests, thunderstorms, or fireworks. One collar lasts for approximately 30 days, so with a pack of 3, you can use it for up to 3 months. 【Product Condition】 ・Brand new, unused, and unopened. ・There is some damage to the outer packaging, but the contents are not affected (please check the photos). If you have any questions, please feel free to ask in the comments. Thank you!