Liza, I'm not sure what you're asking ... but if you are saying that he can walk out of his harness, it is too big.
I've tried 4 different harnesses, and by far this one I found at Petco is the best. It's sort of like a little quilted coat ... very comfy. It velcros in the back, and you can pull it to fit tight, and then you can loosen it as Dolce gets bigger. The two D-rings clasp together, and you can pull up on the D-rings, making the vest even more snug.