4 x 5 Graflok Back Parts- The Springs With Ground Glass and the Viewing Hood: In this lot are 2 of the three parts of a Graflok Back: Part 1; The #31915 frame and its springs that will eventually hold the film holder tightly to the camera back, along with the ground glass, that is free of any scratches, cracks, and chips. Part 2; The viewing hood which pops open strongly and folds, closes and locks nicely. The clips that hold the dark slide are both present.