Ok so I finally got the Knox chest protector in. My chest size is 40ish at best and I don't have rippling pecs and arms like bongs firemen avitar so i went with the small size chest protector since I didn't want it to baloon my suit that much and hence restrict movement. It's almost too small. Granted I know it's not supposed to cover the entire chest but I may have to send it back. Didn't have time to try it with the suit on, but inital thoughts are it's made pretty darn well from what I can see. You can remove the outer neoprane mesh material and wash it which is a good thing. I guess I'll make the final determination later. does anyone have a knox protector?