This is one of those things that when I see it I say "why didn't I think of that"!
It's basically taking an item that already exists and repurposing it for another use. A great use! We've used these in rock climbing, now they have added a rubber grip and renamed it (not knocking the invention at all)! You simply clip it to the handle of your stroller and then hook all the bags on to it so they don't fall off. It's made out of a durable heavy duty aluminum and not the cheap plastic most other gadgets are made out of. Great idea momdadandbaby.com!
You can visit their website for retailers that sell it at TheMommyHook.com