The FSA MegaExo to BB30 Adapter allows you to mate standard FSA cranks with a 24mm spindle to a frame with a BB30 bottom bracket shell. FSA specs this adapter with its smooth rolling, steel cartridge bearings.
FSA machines the cups from aluminum as they're subjected to a pressfit into the bottom bracket shell. So while being lightweight, they are also sturdy and resistant to unwanted deformation that could cause creaking.
The FSA MegaEexo to BB30 Adapters are distinguished by their anodized silver cups. The ceramic version is red. They come as a complete pair with bearings and dust caps installed and are ready for installation -- press them in, install the crank, and go ride.