Alcott Martingale Black Dog CollarA perfect solution for your escape artists, our martingale adventure collars offer a more comfortable solution over traditional choke pinch collars. Simply attach your leash to the D ring and the collar will automatically tighten as your dog pulls on the leash, preventing them from being able to slip out of the collar during your walks together. Five Vibrant Nylon Colors Reflective Stitching Black Neoprene Comfort Padding Three Adjustable Sizes Metal