This clearly has to be where the name comes from.
One word of caution, it is snug. Most Castelli gear is very form fitting, and this is no exception. It is meant to not affect aero drag, and it doesn't.
It is light, blocks the wind in the front, and dumps the heat out the back, great when full winter gear isn't needed, but I have also throw it over my cold weather jerseys for another layer of warmth.