I just fitted these to my Giant Road Bike
They allow for riding with SPD cleated shoes or just your old skanky runners....LOL You just flip the platform accordingly - they work a treat as I don't always find myself in the mood for a full on 30k ride - just want to go for a quick 10K thrash on the bike path and wear my runners.
http://www.shimano.com.au/publish/co...0.-type-..html