Time series Stokes-I spectra of RSP 348 (photometric P = 3.30 d, black lines) showing it to be a hitherto unknown SB2. a. LSD photospheric lines, b. TiO γ(0,0) band head at 7055 Å, c. Hα. Each spectrum is identified with the UT date. The red spectrum in panels b and c is the single star RSP 542 (T_eff≈4000 K) for comparison. Spectra are shifted in intensity for better visibility.