OM-2 Spot/Program (elsewhere) came only in black. OM-2 and OM-2 MD The principal difference between the OM-2 and OM-2 MD models was the provision of a removable cap on the base-plate to permit attachment of the OM system Motor Drive 1 (or the later Motor Drive 2) for film advance at 5 frames per second and the placement of an "MD" badge on the front left face of the camera. The non-MD badged OM-2 cameras needed to go to a service facility to enable attachment of a motor drive. There is some confusion about the MD badge that appears at the 4 o'clock position on some OM-2's, but not on others. The general understanding is that all OM-2's are motor drive and winder 1 or 2 capable (and included the coupler opening and removable cap), at least the U.S. "legally imported" ones from Ponder and Best. The re-worked base plates (and other modifications) were only required for early OM-1 models. It's unclear what modifications (if any) were implemented when the "MD" badge appeared in the late 70's models. OM-2 and OM-2 MD cameras had the hot shoe 2 or 3 for attaching a flash unit. This had the central sync contact plus one other (either in-line or off to the 10-o-clock position when viewed from the rear of the camera) and a single, threaded post on the prism used to secure the shoe or a post with one small recess for a connector pin (Shoe 3). Additionally, the OM-2 and OM-2 MD models had a reset position on the shutter speed dial adjacent to the B setting. This was used to reset the shutter mechanism in the event of mirror lock-up when the batteries were drained. OM-2N MD The OM-2N MD, manufactured from 1979 to 1984, has a smaller upper-case "N" engraved next to the model number on the front plate at the rewind lever and on the top plate, to the left of the prism. Additionally, the re-set function was moved to the top of the camera via the power-switch and the word "Reset" is engraved next to the word "Check" on the top plate of the camera. The "N" model had a new, re-contoured advance lever which had smoother, rounded edges as opposed to the OM-2 and OM-2MD's advance lever's slimmer and sharper edges. The OM-2N MD used hot shoe 4 with two additional contacts above the main