12: For necks 9-11 in. x 1 in. W
14.5: For necks 11.5-13 in. x 1 in. W
16.5: For necks 13.8-15.3 in. x 1 in. W
18.5: For necks 15-17 in. x 1.2 in. W
21.5: For necks 16.1-19.3 in. x 1.5 in. W
23.5: For necks 18.5-21.3 in. x 1.5 in. W
25.5: For necks 20-22.5 in. x 1.5 in. W
*Each dog is unique, please measure your dog's neck to find the correct size and ensure a proper fit. We recommend allowing for 2 fingers to be placed between your pup's neck and a measuring tape to allow for a comfortable fit. If your pup usually wears a size Medium, this does not mean a size Medium will fit as all designers use their own sizing.