The Kenko 12mm UniplusTube DG (extension ring) is an accessory exclusively designed for use with standard AF lenses to shoot subjects at closer distance with higher magnification. Magnification ratio for TUBE 25 is about 1/2 with 50mm standard lens.
Provides perfect coupling with automatic aperture, TTL metering and AE mechanism. Does not support AF operation.
This DG Extension tube has upgraded "Gate-Array IC" circuitry to work better with digital SLRs and some of the digital SLR lenses.
Note! Not compatible with Canon EF-S lenses.