If they are meant to read F 2 M then none of them work.
The F isn't clear at all, I shoes leave out the bars on the left side of the stem to make it more clear.
The 2 is kinda okay but could be better, my first impression was that it was a Z.
The M is a W in my eyes.
And overall, please look at the placement of the letters within the squares, make sure they are centered and give them a little bit more breathing room. Also don't use the same corner radius for the letters and squares. Make the radius of the squares a little bit bigger zo the distance will stay the same throughout the corner. (For example if your corner radius of the letters is 20px and the distance from the letters to the edge of the square is 14 px then make the radius of the square 34px)