This is two weapons built into one. With a one-shot action, the character can change from one use of the weapon to the other. Any two weapons with similar shape can be combined. Historical examples includes the naginata-staff and pike-longbow. One use of this is to conceal a lethal weapon inside a non lethal (and legal) one. The GM is encouraged to give surprise bonuses when the peaceful staff suddenly turns into a deadly halberd.