Get a reliable, secure fit with the No! Slip® Martingale Adjustable Dog Collar with Buckle. This collar's responsive limited closure buckle adjusts perfectly to your dog to eliminate slipping. The buckle's unique design also ensures you'll never have to worry about the collar becoming too tight. This dog collar is excellent for dogs that easily slip through regular collars. For dogs whose neck and head are close in size — like greyhounds — this is a common and frustrating problem. Explore our range of styles and sizes to stop the slipping and find the perfect fitting collar for your dog!