Looks like the flatscreen one is about 25.5", and the regular one is about 29 3/8".
I have one of each, since I changed my mind about monitors after buying the first bezel. The flatscreen one came in today, coincidentally enough, and I have to say I'm a little upset about the difference in width. Of course, my cab is 26" wide, so I'll have to figure out a way to make it work. Ugh!