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The large Kool Collar dog cooling collar is an effective way to keep your pooch cool-a must for dogs at risk for heat exhaustion or heat stroke from their environment or heavy activity. Simply fill Kool Collar with ice cubes (or use the included KoolTube freezer tube for drip-free indoor use) and place the collar on your dog. The Kool Collar simulates perspiration as the ice melts to create an evaporative cooling effect throughout your dog's chest area. Comes in assorted colors only; sorry, specific color requests cannot be accommodated.