I bought this harness for my 10 month old pitbull mix, and it’s my favorite so far! Every other harness he’s had has been such a hassle to put on and take off, and this one makes that process so easy. It doesn’t stop him from pulling, but I honestly didn’t expect it to. An elephant dart wouldn’t slow this dog down. I would definitely recommend this harness to anyone with a bigger dog! For reference, he’s 70 lbs and wearing an XL.