Size small, blue, xdog vest, comes with black package that you could put weight into them, and it has never been worn. It’s too small for my dog, good for up to 35 lbs, or slim dog up to 40 lbs. The XDOG is the newest version of the World’s Greatest Dog Harness. It combines weight resistance with resistance bands to provide your dog with all the health benefits of fitness training with every movement. Exercising your dog has never been easier or more convenient as it only takes about 30 seconds a day to put the XDOG Vest on and take it off. As soon as your dog is wearing the XDOG Vest it is immediately exercising. The XDOG Vest is a great enhancement tool for any lifestyle. It doesn’t matter if you have a canine athlete or a world-class couch potato the XDOG Vest will take your dog’s daily activities to the next level. Thank you for looking.