The back is very basic, canvas material, less rigid that expected for a top tube bag. the bottom and sides could be more rigid to keep loose items more organized. Overall the bag serves its purpose. For 60 plus dollars I expected more. Pricing on this back should be in the $20 range.

My only complaint is that it rattles a bit when the zipper's open, but I guess it's a good reminder if you meant to close it. I haven't tested it in wet weather yet. Fits snug.

Così di primo acchito sembra tutto a posto, verrà provato in modo adeguato appena sarà possibile.