TOTAL CONTROL - The martingale collar is made both for dogs with wide necks like bulldogs and narrow heads like greyhounds. But it's also great for dogs that pull due to it's cinching action MADE FOR ACTIVE DOGS - 100% smooth & durable polyester, these collars are built for comfort and action. Great for outdoor dogs, water dogs, field dogs, and service dogs. Machine washable and weather resistant. SIZING - The martingale collar is meant to be worn loose so that the cinch action creates the control necessary at the right time. This size X-Small collar is 3/8 inch wide and meant for neck sizes from 9 to 12 inches WARRANTY - 100% GUARANTEED - These dog collars are backed by the Yellow Dog Design 100% Guarantee. Covered from fraying, defects, fading, and even chewing. DO NOT USE FOR TIE OUTS! MADE IN THE USA - Manufactured from start to finish by Yellow Dog Design Inc in Greensboro NC. Every time you purchase this product you are directly supporting US Manufacturing and US Jobs. We appreciate your support of our family business!