I wouldn't say interesting, but it's quite functional!
It's a part of the chainstay protection. Bolts straight onto the protection-pad. It's very flexible and won't break even if you bash it into a rock. It's made by Specialized and it's stock on every Stumpjumper here in Norway. Specialized even gives you a couple of extras just for the kicks of it.
Oh cool, yeah well it's interesting because it isn't designed like the other bb mounted guides. Shame you can only get it for a specialized. Thanks for the response.
I think you can buy them without paying for the bike too, though. Specialized has a huge spare parts catalog and if you're lucky they might have 'em.
I'd try asking a dealer!
Jævla bra, rett og slett!