Designed for protective backing behind the body armor's strike face in a hybrid construction, DSM Dyneema's HB51 UniDirectional (UD)inserts for hard ballistic body armor provides ballistic performance and lightweight comfort. Inserts made with Dyneema HB51 are optimized to provide increased stopping power against multiple fragments at no additional weight. The fiber delivers an improvement of 20 percent in ballistic performance over HB2. This enhanced performance enables manufacturers of bullet-resistant vests to offer the best protection from today's new threats.