Attaching the collar to the lid means when you open it, the shanks and whatever hardware you have attached to the collar lift away. The downside is that you need more clearance behind the freezer for the lid to swing open. I've also seen some where there are hinges on both the lid and the freezer, so you can either open just the lid, or open the lid and collar. Mine has the collar attached to the freezer, just because it was the easiest way to build it. I can't say either way is better...