This chest strap has a durable buckle which is adjustable, you can adjust it according to the dogs bust circumference.This pet harness can protect and lead your pet very well because it is sturdy and wear-resistant.It is made of high quality polyester material.There are 3 sizes to choose from: S, M and L.It is an ideal walking supplies for pet.Item Name: Vest Chest StrapMaterial: PolyesterSize Details: Leash[Our Size S]: Length: 100cm - 150cm/39.37" - 59.06", Width: 1.5cm/0.59"(Approx.)[Our Size M]: Length: 100cm - 150cm/39.37" - 59.06", Width: 2cm/0.79"(Approx.)[Our Size L]: Length: 100cm - 150cm/39.37" - 59.06", Width: 2.5cm/0.98"(Approx.)Chest Strap[Our Size S]: Bust: 35cm - 50cm/13.78" - 19.69", Width: 1.5cm/0.59", Recommended Weight: 10kg (Approx.)[Our Size M]: Bust: 46cm - 65cm/18.11" - 25.59", Width: 2cm/0.79", Recommended Weight: 20kg (Approx.)[Our Size L]: Bust: 55cm - 80cm/21.65" - 31.5", Width: 2.5cm/0.98", Recommended Weight: 30kg (Approx.)Notes:Due to the light and screen setting difference, the item's color may be slightly different from the pictures.Please allow slight dimension difference due to different manual measurement.Package Includes:1 x Vest Chest Strap1 x Pet Leash