Ultra Paws Durable Dog Boots Great traction for senior dogs or with hip conditions that have trouble with slippery floors. Flexible, skid-resistant sole performs in wet and dry, hot and cold conditions. Easy to put on with wide split seam top opening - difficult to slip off. Velcro straps for secure closure, with generous foam to cushion the grip. Measure paw width for best fit: Petite 1 ", X-Small 1 ", Small 2 ", Med 2 ", Large 3 ", X-Large 4" wide. Place the paw on a piece of paper and press down on the top, mimicking how the paw spreads when the dog is walking.<br> Mark the left and right sides on the paper and measure the distance between the marks.<br> Compare this to the boot sizes. The width of the paw should be smaller than the boot size. Loosely fasten Velcro closure<br> Wash in cold water and set to delicate cycle<br> Hang to air dry