1. Neck: 17-26.3 inches, 1 inch wide, please measure your dog's exact neck size and add 1-2 inches to make the right size. 2. Made of soft, smooth, light and strong nylon straps with comfortable neoprene padding that your dog will love to wear 3. High visibility reflective light on nylon webbing, if they catch the light of car headlights, street lights or flashlights, they will appear in the dark, useful and safer when walking with your dog at night 4. The buckle made of quick release ABS plastic is durable and makes it easier for you to put the collar on/off your dog; the one-piece chrome-plated D-ring is rust-proof and stronger than the welded D-ring, allowing you to wear the collar with you every day dogs feel safe walking with them