The problem with most martial arts weapons are concealment and training. It’s no use bringing along an obviously deadly self-defense device as you might get picked up by building security personnel or the police. It is also useless to bring along a weapon (or anything else for that matter) if you don’t know how to use it.
These concerns are easily covered by a self-defense baton. The baton works much like a stick used in stick fighting (or eskrima), and the movements are like those of a big knife mainly hacking at the opponent. Just like using a cleaver at a big piece of meat. Additionally, the self-defense baton is concealed in a cylinder and at the press of a button, it expands to a full combat-length stick. It is not a coincidence that being hit straight on while the baton is expanding is not a good experience.
The surprise of having a big stick is usually enough to deter any aggressor.