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Nikon

Nikon FPW00902 AI 27.5mm Extension Ring

★★★★★3.7 (53 reviews)

Enhance Your Macro Photography with Precision The Nikon PK-13 Auto Extension Ring is designed to extend the macro capabilities of your Nikon AI lens. This 27.5mm macro extension tube provides meter coupling on all AI compatible SLR/DSLR cameras, allowing you to achieve greater magnification and ...

$58.00*
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*Price sourced from Amazon.com. Last updated:Jul 14, 2026.Price and availability are subject to change.

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Overview

Enhance Your Macro Photography with Precision

The Nikon PK-13 Auto Extension Ring is designed to extend the macro capabilities of your Nikon AI lens. This 27.5mm macro extension tube provides meter coupling on all AI compatible SLR/DSLR cameras, allowing you to achieve greater magnification and detail in your close-up photography.

Key Features

  • Nikon AI 27.5mm macro extension tube
  • Auto diaphragm, full aperture metering
  • For Nikon AI manual focus SLR cameras
  • Fits some Nikon AF and digital SLRs
  • Compatible with AI and some AF lenses (not G, DX)

Specifications

  • Type: Macro Extension Tube
  • Length: 27.5mm
  • Compatibility: Nikon AI manual focus SLR cameras
  • Lens Compatibility: AI and some AF lenses (not G, DX)
  • Mounting: Nikon 1

Key Features

Nikon AI 27.5mm macro extension tube

Auto diaphragm, full aperture metering

For Nikon AI manual focus SLR cameras

Fits some Nikon AF and digital SLRs

For AI, some AF lenses (not G, DX)

Specifications

Type
Macro Extension Tube
Extension Length
27.5mm
Metering Support
Full aperture metering
Diaphragm Control
Auto diaphragm
Camera Compatibility
Nikon AI manual focus SLR cameras, some Nikon AF and digital SLRs
Lens Compatibility
For AI, some AF lenses (not G, DX)

Pros & Cons

👍 Pros

  • Specifically designed as a 27.5mm macro extension tube, providing a precise magnification for close-up photography.
  • Supports auto diaphragm functionality, allowing for consistent exposure control across different apertures.
  • Enables full aperture metering, ensuring accurate light measurement for proper exposure settings.
  • Compatible with Nikon AI manual focus SLR cameras, extending the life and utility of classic gear.
  • Can fit some Nikon AF and digital SLRs, offering versatility across certain modern camera bodies.

👎 Cons

  • Primarily designed for Nikon AI manual focus SLR cameras, limiting its use with non-AI or other brand camera systems.
  • Not compatible with Nikon G and DX lenses, which restricts its application with many contemporary Nikon lenses.
  • The 27.5mm fixed extension ring offers a single magnification, lacking the flexibility of variable extension tubes or zoom lenses.
  • As an extension ring, it does not contain optical elements, meaning it will not enhance the optical quality of the attached lens.
  • Requires a clear understanding of macro photography principles to achieve optimal results, as it changes the lens's focal plane.

Frequently Asked Questions

This extension ring is a 27.5mm macro extension tube designed to allow your lens to focus closer than its normal minimum focusing distance, enabling macro photography.
It is compatible with AI and some AF lenses, but specifically not with Nikon G and DX type lenses.
Yes, it supports auto diaphragm control and allows for full aperture metering, which helps in maintaining correct exposure settings.
Yes, it fits some Nikon AF and digital SLRs, although its primary compatibility is with Nikon AI manual focus SLR cameras.
This is a 27.5mm extension ring, which will increase the distance between your lens and the camera sensor by that specific amount.

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