Material of this Chain Dog Necklace: It's 18K gold plated 304 stainless steel chain, which is light in weight, burden-free, and anti-rust and wear-resistant. Adjustable size of cat necklace: Chain width is 0.25 inches, four sort of length can choose. Respectively are 7 inches, 10 inches, 12 inches , 15 inches and the length of the extension chain is 5cm (about 2 inches), could be extended to the length you need ,which can be adjusted to fit the necks of most puppies and small dogs. Great pet chain necklaces are suitable for cats, kittens, Chihuahua, Dachshunds, Bichon Fries ,and small dogs and other small pets as well. This pet gold heart necklace is perfect match with most clothing, and more cute looking with clothing such as Hawaiian style, sunglasses, hats. Perfect gift-This heart necklace is gorgeous and fashionable. High polished craftsmanship makes the surface shinny and smooth, comfortable, makes your pets look more charming and joyous. So we believe your pets will be happy to own this necklace.