http://www.nikonchat.com/nikkor-300mm-f-4/
Is the Nikon AF Zoom-Nikkor 70-300mm f/4-5.6G AF with Nikon D3100?
Not only Nikkor AF-S and AF-I can autofocus the entry level nikon digital slr bodies. This information is in the manual must be looking at the AF-S 70-300 mm f/4.6-5.6G IF Nikkor lens All the AF can be mounted in the entry-level cameras, but will have to manually focus with electronic rangefinder in your viewfinder
Nikkor 300mm f/4 AF + Kengo Teleplus PRO300 DGX AF 2x on D700
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