The new Oasis maxi prom collection is exclusive to John Lewis online. This bandeau style features a delicately embellished neckline on a soft pleated bodice, with a fluid floaty maxi skirt. Brand : Oasis. Dress Shape : Prom Style. Material : 100% Polyester. Neckline : Open Neck. Size : 12. Sleeve : Strapless. Washing Instructions : Hand Wash.