This collar features patterned silhouettes of unicorns with shooting stars and rainbows on a dark blue background. Martingale collars are also known as Greyhound Collars or Humane Choke Collars. The Martingale Dog Collar was designed for Sighthounds (ie, Greyhounds, Whippets, Italian Greyhounds, Borzoi, Saluki, etc) because their necks are larger than their head and they can slip out of traditional side release dog collars; these collars have gained popularity as training dog collars with other breeds in the recent past because trainers prefer the humane choke aspects.
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