I have got one that I wore once as my surgeon wouldnt let me wear it (doesnt like them) so if you would like to buy it off me then you are more than welcome..
It is a small as they come in small, medium and large and I was a 34 backsize so it should be fine…
Let me know if you are interested and you can have it for £20 plus whatever it costs me to post it…they cost £35 new…