What would an ideal elegant top for her to dress?

My wife has the habit of wearing very low neckline dresses with more frontal visibility. She loves exposing her cleavage well. What would an ideal elegant top for her to satisfy her way of dressing? A shirt with top buttons unbottoned or a upper wear with a full front zip? I need to present one for a occasion soon|||http://www.chicos.com/store/home.jsp?CMP鈥?/a>





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