HS Sprenger Chrome Steel Training Collar HS Sprenger Training Collar Chrome-plated steel material ensures the necklace will last for many years. This collar with rounded spikes is indicated for dogs "unaccustomed" to walking without pulling. The pressure exerted by the barbs against the neck of the animal when it pulls, will gradually correct its behavior. It also has a semi-hogo chain that closes at the pull. The collar has a central plate that distributes pressure evenly. All Sprenger brand products are of superior quality and unbeatable reputation. Measurements: 41 cm length - 1.5 cm width - 2.25 mm thickness - up to 20 kg 58 cm length - 2.2 cm width - 3.2 mm thickness - up to 40 kg 63 cm length - 2.5 cm width - 4 mm thickness - up to 70 kg