The Titan Easy-On Dog Prong Training Collar with Buckle is argon welded and chrome plated for maximum strength and durability. Featuring a convenient buckle for easy removal, it will not tarnish, rust or break. Extra links and vinyl comfort tips are available for this training collar. Available in 2.0 mm x 4" 3.0 mm x 18", 3.3 mm x 20" and 4.0 mm x 22". Chain training collars are safe, effective training tools with proper use. They are not to be used for tie out.