Open-Back Long Prom Dress: Jessica Angel 347Strike an elegant pose in this sleek long mermaid prom dress 347 by Jessica Angel. Sleek and sexy for prom, galas, and other black tie events, this beautiful long formal dress smooths over the curves from the v neckline to the floor. In misses and some plus sizes, this long designer dress has thin shoulder straps that lead to the open back, while the mermaid skirt hugs the hips before pooling into a train that provides the drama. Made in the USA, this