Observed mass-loss rates of O stars in NGC 346 (including SSN 7) as a function of stellar luminosity compared to theoretical and empirical relations. The position of both binary components of SSN 7 are marked by black stars. The data is complemented by O stars from Rickard et al. (2022). Apparently single stars are shown as filled blue squares and known muliple systems as open blue squares. In the background the empirical relation of main-sequence O-type stars from Rickard et al. (2022) is included as dashed black line. In addition, we show the theoretical relations of Vink et al. (2001) and Björklund et al. (2023) for main-sequence stars as dashed yellow and dashed red line, respectively.