Herm Sprenger HS Chrome 22" 3.0mm Medium Prong Collar For Dogs MADE IN GERMANY, Size Medium, 3.0mm 22", Chrome plated steel wire With Center - Plate and Assembly Chain, Adjustable length Classical version for dog training, Heavy duty links for STRENGTH & DURABILITY More flexibility between the dog collar and the leash through the swivel, Guaranteed against rust, tarnish or breakage Select the proper weight and size for your dog. This training collar must be fitted correctly to work properly. Unfasten one of the links and place the collar around dog's neck before refastening. Quick release snap may also be used to fasten the collar around neck. Extra links may be added or removed to make a comfortable snug fit. Attach lead to "D" ring at top of the collar. This collar is intended for use ONLY while dog is on leash and attended.