The Canon EP-EX15 Eyepiece Extender extends the eyepiece by 5/8" (15mm) from the camera body and reduces the viewfinder magnification by 30%.  This is useful for eyeglass wearers and others who wish to prevent the tip of their nose from touching the camera body.  It also prevents condensation or fogging.

The EP-EX15 fits all Canon EOS cameras except the EOS 1D Mark III, A2, A2e, 3, 5 and Elan II-7N series.