We present high resolution J-band spectroscopy of V 393 Sco obtained with the CRIRES at the ESO Paranal Observatory along with a discussion of archival IUE spectra and published broad band magnitudes . The best fit to the spectral energy distribution outside eclipse gives T _ { 1 } = 19000 \pm 500 K for the gainer , T _ { 2 } = 7250 \pm 300 K for the donor , E ( B - V ) = 0.13 \pm 0.02 mag . and a distance of d = 523 \pm 60 pc , although circumstellar material was not considered in the fit . We argue that V 393 Sco is not a member of the open cluster M7 . The shape of the He I 1083 nm line shows orbital modulations that can be interpreted in terms of an optically thick pseudo-photosphere mimicking a hot B-type star and relatively large equatorial mass loss through the Lagrangian L3 point during long cycle minimum . IUE spectra show several ( usually asymmetric ) absorption lines from highly ionized metals and a narrow L \alpha emission core on a broad absorption profile . The overall behavior of these lines suggests the existence of a wind at intermediate latitudes . From the analysis of the radial velocities we find M _ { 2 } / M _ { 1 } = 0.24 \pm 0.02 and a mass function of f = 4.76 \pm 0.24 M \odot . Our observations favor equatorial mass loss rather than high latitude outflows as the cause for the long variability .