Help with shoe size conversion mm to inches

Purchased online a pair of Pine Tree sneakers (Sang Moo SA), martial art workout shoes, in men's shoe size 9.5 inches. However, on the tongue of the shoes is denoted 290mm / 9T (as the shoes size ??). No where else on the shoes is there a size cited in inches. So I assume that the measurement of 290mm / 9T is representative of a shoes size. Unfortunately, I don't know whether it is representative of a man's size: 9.0 inches or 9.5 inches. As previous mentioned above, I ordered a man's size 9.5. The seller has been of no help by virtue of not addressing my issue. I would appreciate any assistance resolving this issue. The seller has given me a rather narrow time window for RMA, therefore, time is of the essences.

Thank you,
Jido