Medium Large Dog Collars 21" Nylon Buckle Dogs Collar Red Pink Green Black Blue Here are some really colorful medium to large dog collars. These are 21 inch nylon adjustable contour side release buckle type, with a D ring and slack adjuster. The buckles are very secure. The collars are 1 inch wide, they are ideal for 40 to 60 lb dogs. The neck circumference is about 20 inches, biggest, down to about 16 inch circumference. You could make it somewhat smaller, but I think it would be to tight for a medium dog, unless it's a Greyhound or something. Collars, as you can see, come in red, pink, lime green, black blue. Just use the drop down to select. Thanks for stopping. Please visit my slow growing store, read about me, my policies and view other items that may interest you. Also, I would be honored to be added to your saved seller list. **I always have money saving volume discounts on most items** David - thediscountretailer