The Rockler Perfect Fit Dado Jig is a great tool for making fast, repetitive Dado cuts. However, the factory only discusses how to use this wonder tool with a 1/2" router bit; which limits its usefulness to only making Dado's in the 1/2" to 1" range.
This video shows how you can use the Rockler Dado Jig to make perfect Dado's using larger size router bits, making it possible to cut much larger perfect Dado's where needed.