Haute Dauge Best in Show by H.D. Martingale Jeweler Link Style Show Chain for Dog Show or Training Collar - Chrome Martingale Chrome Show Chain | 1.35 mm | Size 18 fits maximum neck circumference of 16 inches depending on thickness of neck fur. Read sizing instructions. Electro-plated smooth finish over brass. Even number size increments An attractive, light-weight, slender chain for show dog presentation. Subtle sparkle quality with movement. Image with dimensions is for illustration of size comparison of the two link sizes that are available in the Haute Dauge Martingale Collars. Read Product Description Section for more information View all images to decide which link size is appropriate for your Dog. The Size Number is for reference only. Read the Bullet Point information for the collar's maximum neck circumference. For the initial collar fit, measure around the widest part of the dogs head and the dog's neck. Add 1 to 2 inches to the largest measurement. This will ensure that you can easily slip the collar over the dog's head. Choose chain length accordingly.