SDSS spectrum of the z_em = 1.94 QSO J 0815+2640. The C i λλ1560,1656 absorption lines detected at z = 1.681 are indicated, along with the presence of several low-ionization metal lines at the same redshift. Among the latter, the simultaneous detections of Si ii λ1526 and Al ii λ1670 lines were required by our detection algorithm to minimize the probability of coincidence. In this system, relatively weak Fe ii λ1608 absorption is also observed.