Puts it into the water, twisting it, then put it into the fridge for a few minutes and take it out. The cooling effect of the scarf will be more obvious. Don't hesitate indulge your furry friends with this cool ice collar. It's durable and will not deform after multiple cleaning. Features -Color: Pink - Material: PVA -Size S: 19-31cm/7.48-12.20inch(neck circumference) -Size M: 31-42cm/12.20-16.53inch (neck circumference) -Size L: 42-57cm/16.53-22.44inch (neck circumference) - Pets will feel very hot in the summer and other hot days, and they can rely on this cooling collar to dissipate heat. - The scarf can weaken heat out of your pet and releases it with ease. - K eeping dog or cat cool for a long time, allow your pet to play, rest or sleep comfortably. - This cooling collar is safe for pets, adults, kids and the environment. - It's a simple solution to avoid overheating and dehydration for hot weather.