Size xs solid gray fits 13"-17" chest size 8-14lbs Thundershirts are amazing! my dog is an outdoor farm dog that WILL NOT get in a vehicle. He doesn't like inside either. it stresses him out. I bought one for him to ride to the vet & for us to try traveling with him in general and I think it helped a LOT. No, it's not a magic cure but it did make a tremendous difference in his anxiety while riding. Basically it gives them a long lasting hug. Highly recommend it for any pets with anxiety. Smoke free pet free home. (The pups are outside) Usually ships within 48 hours. bundle and save on shipping. No reasonable offers refused! Thanks for checking out my closet.