The MD-12 was introduced way back in 1980 replacing the motor drive MD-11 in 1977. Most changes are internal rather than external such as meter off after lifting your finger off the trigger button, the MD-12 will advance the film immediately when you have full depress the button.
This Motor Drive from Nikon is impressive enough, performs almost flawlessly in operations. If you can still live with the moderately slow 3.5 fps and the lack of an auto film rewind feature part is its dependability and ruggedness. I don't think any MD-12 users have doubt this fact. But most of all, you shouldn't think the motor drive is an special accessory. Just think of it as a normal supplement to your camera for a more enjoyable photography. Other than the slight drawback of additional weight added on to your compact body, it presents some very strong reasons to consider such added on.
This is used, the outer area, shows signs of age and use. The bottom has some chips of paint missing, but it wouldn't affect performance