Theory Dezzie Tank in Peach. - size L (also in ) Theory Dezzie Tank in Peach. - size L (also in ) 100% silk. Dry clean only. Neckline keyhole with tie closure. Elastic smocked waist. THEO-WS808. H0202502. Theory is a visionary concept for modern intelligent fashion forward people. Founded in New York and made by the finest of fabrics, this makes the working everyday person feel powerful, ready to face their day.