Evolutionary (M_ev) vs. spectroscopic (M_spec) masses for the analyzed O-type stars in N11 B. The M_spec values were obtained with PoWR modeling, and the M_ev values were derived with BONNSAI by introducing PoWR-obtained parameters. The objects are indicated with their PGMW # ID. In addition, the two Sanduleak O-type stars (not in N11 B) also analyzed here are shown (green squares). A one-to-one relation is indicated (dashed line) as a reference. Triangles represent lower limits (see text for details). The gray color indicates confirmed SB1 binarity, and the member of a cluster is shown in black.