I'm planning on buying an extendable baton for self defense (most likely never going to have to use it). I'm just curious if I'm allowed to have one in China since in the United States it's allowed. I couldn't really find any information on the web so I thought I would ask here.
According to The Washington Post, expandable batons are legal in China mainland and illegal to carry in the streets in Hong Kong.
in the states it's allowed.
That's incorrect. See this blogpost:
California is the only state where expandable batons are illegal to both own and carry. In Massachusetts, New York, and Washington D.C. batons are legal to own at home but illegal to carry outside, open or concealed.
Also mostly illegal to carry in France.