Stylish, durable, and simple to clean! Made from super strong, smooth flex-poly strap, all-weather materials that are comfortable for pups to wear and dirt- and odor-resistant. Easy to clean, Dirt & Oil Resistant, Waterproof X-Small: Neck Circumference = 7"-10" Strap Width = 1/2" Small: Neck Circumference = 8"-12" Strap Width = 3/4" Medium: Neck Circumference = 12"-15" Strap Width = 3/4" Large: Neck Circumference = 15"-18" Strap Width = 1" X-Largle: Neck Circumference = 18"-23"Strap Width = 1"