The NO-M1-W2903 was developed for use with the NO-M1-1a - Mantus Infantry Power Armor, it became available in YE 29.
Built in to the side of each of the power armors arms is a retractable one foot long blade. This blade is formed from perfect diamond and so is both very damage resistant and extremely sharp, sharp enough to cut through most materials with the strength of the power armor behind it. However in order to deal with other targets the power armor is capable of projecting a force field around the blade which protects it from being damaged by more powerful weapons. This force-field isn’t invulnerable though, and when activated relegates the sword to little more than a powerful bludgeoning weapon.