Part #: CB3-4827. It's called light shield plate according to 5D MII parts catalog manual. Anyone knows where to buy?
I forget to put it back on after I cleaned my viewfinder (a little nerves to do this), when I realized that, it's too late to find out where it is.
If anybody wants to try, here is the tutorial link: http://shimworld.wordpress.com …-the-5d-mk-ii-viewfinder/