The optical design and coating are optimized to reduce the flare and ghosts that are prone to occur with digital cameras. The quick and quiet inner focusing and ring-type USM autofocusing ensure that exclusive photo opportunities are not missed when shooting insects and small animals. The lens mechanism is designed to ensure that it fits only EOS DIGITAL SLR cameras designed to take EF-S lenses. It is equipped with a special attachment indicator and protective rubber mount ring to prevent mistaken attempts to attach it to other EOS SLR cameras, and to prevent damage to the camera body. 

NOTE: Can only be used with digital SLR cameras that support EF-S lenses. Compatible with EOS Digital SLR cameras: EOS 50D, EOS 40D, EOS 30D, EOS 20D, EOS 20Da, EOS Kiss X2/DIGITAL REBEL XSi/450D, EOS Kiss F/DIGITAL REBEL XS/1000D, EOS Kiss Digital X/DIGITAL REBEL XTi/400D DIGITAL, EOS Kiss Digital N/DIGITAL REBEL Xt/350D DIGITAL, EOS Kiss Digital/DIGITAL REBEL/300D DIGITAL (as of August 2008).
 
 
 
Filter size: 52mm
 
 
Max aperture: f/2.8
 
 
With ring USM motor