Ah you bought it used. Yeah, there's an extension tube, and of course the whole battery adapter that fits in the battery well of the XL1 and Xl1s series camera. (I put mine in a drawer somewhere... hope I can find it one day.)

Did you get the diopter adjusted properly? It's a bit stiff to move, which is kinda nice in that it won't get bumped.

Worked like a charm. Thanks Richard! You weren't kidding about it being stiff to move.