cat converter question

are there any differences between the cat converters for flex fuel and non-flex fuel vehicles? i'll never run the e-85 so would it be a problem to replace my cats with the non flex fuel cats? just running gas everything should be the same right?

I took a quick look at rockauto.com and they listed the same part number for the cat with flex fuel and without. So it seems there is not a special cat for flex fuel.

//2000CAYukon