Canon Extension Tube EF25 II ring set

Canon Extension Tube EF25 II zoom ring

Canon's original 25mm zoom ring. II version, meaning this works with EF lenses as well as EF-S lenses. The zoom ring transmits electricity, meaning aperture and focus information is transmitted between the lens and the body.

The zoom ring is placed between the camera body and the lens, which results in a reduction in the focusing distance of the lens. Zooming out reduces the light output of the lens.

This zoom ring set works with Canon DSLR bodies and Canon EF and EF-S lenses.