The FM3A'S film transport consists of high-strength hardened metal gears and moving parts, mounted on clusters of ball bearings.

The vertical metal shutter utilises precision tapered high-strength aluminium alloy blades and oilless self-lubricating bearings.

This special flat "pancake" lens was manually focused on the FM3A, but contained a CPU which could communicate focal distance to Nikon's later autofocus (AF) camera bodies.

In manual mode, the camera is completely mechanical in operation, and only requires batteries for the light metering information system.

In aperture priority mode, the batteries continued to power the meter, but are also utilized for shutter timing and the exposure control electronics.

These cameras required complex computer and processing mechanisms, and especially in their amateur and consumer versions, were known for neither their ruggedness nor a long service life.

Nikon instead marketed the camera to serious amateur and professional photographers who were desirous of the highest possible quality and precision of control, and a service life estimated not in years, but decades.

Many photographers, professional and amateur alike, switched to digital, resulting in a huge decrease in film SLR sales.