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Opteka Auto Focus DG Macro Extension Tube Set for Select Nikon SLR Cameras

Extension tubes are designed to enable a lens to focus closer than its normal set minimum focusing distance
Designed with all the circuitry and mechanical coupling to maintain auto focus and TTL auto exposure with Nikon SLRs
Contains three tubes of different length a 13mm 21mm and 31mm
Glass-free Lightweight
1 Year Opteka Warranty