The steeper parabola of focus makes the image in and out of focus more brightly in the viewfinder. The Ee-S focusing screen is not suggested for slower lenses because it is not bright. The canon Ee-S comes with a tweezer like tool in the kit which make it easy to insert the focusing screen in to your camera.
Features
Specifications
Kit Content
Canon Ee-S Focusing Screen
User Guide
Manufacturer Warranty
Package Information