The Tartan roll neck by Worthy Dog is a stylish and warm sweater. 100% acrylic, this super-comfy double-knit sweater will make your dog look adorable. The sweater features a “button hole” in the back so that you can conveniently hook your pet’s lead to his/her harness.SIZEWEIGHT (LB)LENGTH (IN)GIRTH (IN)XS 5-9 9 12-15SM 8-13 11 14-17MD 12-19 14 17-21LG 18-28 16 20-24