They let you get much bigger magnification at close-up focussing distances. More rings = more magnification.
These have both mechanical AF drive and electrical connections to allow auto focus with AF, AF-D, AF-S and AF-P type Nikon lenses or you can manually focus if you prefer.
There are designed to be used with Nikon Macro lenses (Micro Nikkor) but can be used with regular (non-macro) lenses as well with vary degrees of success - have fun experimenting..
Fully tested and working with my 105mm AF-D macro lens. See result of test shots focussed on the P of the champagne bottle table decoration. Super close up with 3 tubes attached. And another couple of other examples with non macro AF-S and AF-P lenses to prove everything is working correctly with those types of lenses.
Boxed with original instructions (tiny tear repaired with sellotape) and both rear and front caps. Note: my camera and flash shown in a couple of photos are not included! :-)
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