The Neewa Sled Pro Harness is a pulling harness for dogs, made in polypropylene, with padding on the neck and ribcage areas, to provide absolute comfort when the dog is pulling. The special X-back construction provides uniform distribution of pressure over the dog?s entire body. Reflective inserts make sure your dog is clearly visible at night. Made entirely with non-allergenic breathable materials, it is extremely comfortable for the animal. The Sled Pro Harness has been designed for wolf-like dog breeds, and in particular for purebred Nordic dogs such as the Siberian Husky, the Alaskan Malamute and Greenland dogs. If your dog is a different breed, we recommend either our Adjustable Racing Harness or our Perfect-Fit Harness (aka Adjustable Sled Pro Harness on Amazon). This joring harness is perfect for all pulling activities and types of dog exercise and, in particular, for dog sledding, dog trekking, canicross, skijoring and bikejoring. IMPORTANT: Please choose the right size for your dog carefully, using our guidelines on this page. If you are undecided between two sizes, it is usually better to choose the larger one. SIZE GUIDE (measure your dog's neck circumference and back length): Small - Neck 16in, Back 19in, Weight 40-49lb Medium - Neck 17in, Back 22in, Weight 49-57lb Large - Neck 18in, Back 24in, Weight 57-66lb X-Large - Neck 20in, Back 25in, Weight 66-84lb XX-Large - Neck 22in, Back 27in, Weight 84-99lb XXX-Large - Neck 23in, Back 29in, Weight 99-132lb