Reinforce II

Magical Girl Lyrical Nanoha A's : She appears briefly during the last seconds of the series. Magical Girl Lyrical Nanoha StrikerS : Reinforce II is a smaller version of Reinforce that has been accepted as a member of Hayate's task force in the Time-Space Administration Bureau; she even wears the uniform. She can be summoned as a hologram from the Schwertkreuz, and promotional pictures for StrikerS show a very solid Reinforce II accompanying Hayate as well. Reinforce II (pronouced "Zwei") is apparently solid, and needs to eat and sleep daily; she has a "room" of sorts in Hayate's bag. She holds the rank of Sergeant Major and serves as Hayate's SNCO/ Chief of Staff in Lost Property Management Division 6.

In the anime, she is shown capable to unifying with other Wolkenritter members (Vita and Signum) to boost them in battle, although because of their incompatibility, their union is not as good as Hayate's. When unifying with them, their clothes change its color to white. (Source: Wikipedia)