Herm Springer German made stainless steel. Excellent for teaching heel, sit, stay, whoa, etc. Proper fit is achieved by adding or removing links. Just snap them in or out.
We prefer the steel "pinch" type dog training collars to choke chains as we have found their use to result in easier and faster training for both the dog and the trainer. We suggest that teaching "heel" is a good place to start with the pinch collar.
First adjust the collar by removing links or adding lengths to get a "good" fit - a fit where the dog will be comfortable when he is in the proper position but will become uncomfortable when he gets out of position. If the dog is wearing a regular collar, place the pinch collar in front of the regular collar and check frequently to be sure the pinch collar is not hanging up on the regular collar. We suggest keeping the pinch collar low on the dog's neck and walking at a slow but steady pace the first few sessions using a large (25' - 30') circular, figure 8, or box pattern. After several sessions, you should be able to progress to a varied pace, and quicker and sharper turns and stops. Placing the pinch collar higher on the dog's neck usually causes more discomfort and a better response in dogs that have not responded after several sessions. Also, a collar with smaller diameter prongs will usually elicit a better response for dogs that have been slow in responding.
We have found the pinch collar to be especially useful in teaching "heel", "sit", "whoa", "stay", and "here". Our own view is that choke chains and pinch collars should not be used on pups under six months of age. These collars should only be during training sessions and should NEVER be left on unattended dogs.