Material:316L Stainless Steel,Heavy Duty O Ring: Large fully-welded O-ring very easy for leash attaching. Strong & Durable - Stainless steel is incredibly strong and will never rust or tarnish, making it the perfect material for a metal dog collar. Each dog collar is made of solid stainless steel, and has a polished finish. Stylish Comfort - The wide curb chain looks great around your dog's neck while remaining comfortable for hours of wear, and will not ruin your dog's coat like many choke collars or prong collars that dig into the skin. SIZE GUIDE: Length: 12“-34',The total length included 2 O-Rings. Width:17mm Collar length should be 2.5' longer than the widest part of your dog's head. Exquisite Workmanship: Each features a hexagonal link design, meticulous workmanship, polishing, surface smooth, the smooth chain will not pull out your dog's fur, keeping your dog happy and comfortable!