Petsmart in canada used to carry a Martha Stewart line which had the best harnesses. I bought one xs size 10 years ago, and a second s size 8 years ago for the other dog. I still have them and it's the only one that fits my chorkie with a 18.5cm neck and 28cm chest comfortably while still being stiff and rugged. The straps were very thick but thin so the dogs don't get any chafing. She's mad cause I just manhandled her for measurements.

Anyways, I can't find them anywhere on the petsmart anymore and I'm wondering if she just stopped making them all together. They come in two colors, pastel pink with a light pastel green stitching and in a warm medium blue with a dark hot pink stitching in case you can still get the products wherever you are.

I dunno why all the awesome things have to discontinue.

Edit: this is the closest I could find that is similar, though the colors are different now. Size 12 starts at 11inch chest. I feel like there used to be a size 10 and that's what my chorkie is in. Anyways, good luck. https://www.amazon.com/Martha-Stewart-Classic-Webbing-Overlay/dp/B074JM8MDK/ref=mp_s_a_1_19?dchild=1&keywords=martha%2Bstewart%2Bpet&qid=1629404942&sr=8-19&th=1&psc=1