Nikon BR3 Reverse ring 52mm

The Nikon BR-3 is a vintage camera accessory designed for macro photography when using a reversed Nikon F-mount lens.
When you reverse a lens for close-up work—usually by using a reversing ring like the Nikon BR-2A—the rear element faces forward toward the subject, leaving it exposed and without filter threads. The BR-3 solves this by attaching to the bayonet mount at the back of the reversed lens and providing a 52 mm female filter thread.

Key purposes:

Protection: Lets you mount a clear or UV filter to shield the delicate rear element from dust, scratches, and accidental contact.

Accessory mounting: Allows the use of standard 52 mm screw-in filters, hoods, or other accessories on the reversed end of the lens.

Light control: Can help reduce flare or improve contrast when paired with a short hood.

Made of metal with a simple, compact design, the BR-3 is durable and small enough to keep in any macro photographer’s kit. Though it’s an older Nikon accessory, it remains a practical tool for anyone shooting extreme close-ups with reversed F-mount lenses.