Isn't this a clever little idea for a back or front infant carrier! Via etsy seller Naturally Crafty Shop. I don't see it in her shop anymore:-( But I bet you could DIY this! (I know always say that.) I don't quite know how she made hers but you could make the shell with fabric and then attach to your carrier with either velcro or sew on snaps. I know someone who might like one of these;-) To make the shell you'd have to make it concave which wouldn't be hard. Then add the shell design and bind the raw edges. It looks like the shell below uses some kind of leather or vinyl for the trim and shell details.