The size is a medium. I'd suggest that it's slightly smaller than a normal medium (or maybe I've been getting too much takeaway lately). Never been worn, only to try on.
https://www.constant-e.com.au/hrnsw/
https://www.constant-e.com.au/HRNSW/hrnsw-hoodie.jpg
https://www.constant-e.com.au/hrnsw/
These are about $60 + $20 p&h when new. I'll take $50 ono. Free postage.