Upper panel: model fit (heavy curve) to all the hydrogen and strong helium lines (thin curve) available in our high S/N, low-resolution optical spectrum of KIC 02697388. The fit was done using a 3D grid of NLTE synthetic spectra (T_eff , log g, log N(He) /N(H)) in which the abundances of C, N, O, S, Si, and Fe were held fixed at amounts consistent with Blanchette et al. (2008). Lower panel: similar, but for a 3D grid of NLTE synthetic spectra without metals.