Dimensions: 2 size available. Small Approx 16" x 9". Suit for pets up to 6 lb. Large Approx 18" x 10.5". Suit for pets up to 12 lb Such as Cats,Minlature Pinscher, Chihuahua, Yorkshire Terrier, Pomeranian, Mini poodle, Miniature Schnauzer, Teddy cups or other similar types of pets. Special hook design which connects to pet's collar in order to protect your pet's safe.Breathable mesh material makes the pet comfortable. Contraction rope design is adjustable according to the pet's neck circumference up to 16.5-18.8" according to different sizes. High quality plastic buckle is easy and convenient to adjust the length.Update Zipper design is easier for pet to get in and out,Durable. Apply to: Puppy, Kitty and other little pet,can't fit for the heavy duty pet.any question, please feel free to contract us.