That is the back, replacing the original ground glass frame on the camera using the Graflok adapter. It does have the blackout plate - that is the part with the two blue knobs. Suction/vacuum is produced by a rubber bulb which is attached to the small steel tube located in the upper right hand corner, below the Schneider-Kreuznach lettering. If the original one is not there, a replacement could probably be found.
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