Olympus Recordata Back 3
Mounted on the OM body (OM-4, OM-3, OM-2n und OM-1n), this unit is capable of imprinting a date coded year, month and day, or a time coded day, hour and minute in the lower right corner of the picture (with camera held in the horizontal position).
If no imprinting is required, switch off the liquid crystal display and the unit will function as an ordinary back.
It can be left on the camera as a standard back permanently, and also be used as a watch. The maximum year that can be imprinted by Recordata Back 3 is 2009.