This listing is for a lovely size Medium popover tunic top from J. Crew.  The top is a lighter weight blue chambray fabric and has a folded collar with buttons at the top.  There is an upper left front pocket.  The sleeves are long.

The tunic is in very good pre-owned condition with gentle wear and the measurements are as follows: 

Bust is approximately 21"/42"

Length is approximately 31" in front, slightly longer to 32" in back

The fabric tag has been taken out but I think this is cotton.