“Nice but very small”

“I bought a pair of these in the La Sportiva size 39 which STP posted as a men's size 7. I was skeptical they would fit, and indeed, when they arrived, they are very small. The shoe box, in fact, says size 6.5+. I am not sure what the + sign means, but it does not mean that they are size 7. I have not yet returned them because they are very nice approach shoes and I may be able to wear them in the summer without socks- I have yet to make that decision.”