Coastal Pet Titan dog training choke/collar is excellent for gentle control. This extra heavy quality chain is argon welded and chrome plated for maximum strength and durability. It will not tarnish, rust, or break. Recommended for professional training. Use only when dog is attended on leash. This choke chain is sized by total overall length, including the rings. Measures 26-inch overall length and 4.0-mm link diameter.