Promaster Spectrum 7 Extension Tube Set for Nikon F wind ) If you only want

) If you only want to carry one lens for pretty much everything

The internal dimensions are 23 x 17

Provides a 25mm extension for FD lenses

and it includes two comparator discs if you're planning to use it as a pocket comparator

Promaster Spectrum 7 Extension Tube Set for Nikon F wind ) If you only wantA set of three extension tubes for Nikon F mount: 12mm, 20mm, and 36mm. These tubes have the electronic contacts necessary to maintain autofocus and autoexposure capabilities. If you're curious about dabbling in macro work, this is an inexpensive way to get started. Good working order, light cosmetic wear. Includes rear cap; lens and camera sold separately.