NOTE: This information is not provided as legal advice. Always consult a lawyer and seek legal guidance.
California Expandable Baton Law
Penal code 22210 described as a leaded cane. California Expandable Baton Laws are pretty simple, NOT legal in nearly any situation. Not legal to own, carry, possess, sell or nearly anything else. I would suggest avoiding California Expandable Batons unless you have special privileges.
Here is the law on Expendable Batons in California:
California Expandable Baton Laws
2007 Dangerous Weapons Control Law 12020 thru 12040 Unlawful Carrying and Possession
ARTICLE 2. UNLAWFUL CARRYING AND POSSESSION OF WEAPONS 12020. (a) Any person in this state who does any of the following is punishable by imprisonment in a county jail not exceeding one year or in the state prison: (1) Manufactures or causes to be manufactured, imports into the state, keeps for sale, or offers or exposes for sale, or who gives, lends, or possesses any cane gun or wallet gun, any undetectable firearm, any firearm which is not immediately recognizable as a firearm, any camouflaging firearm container, any ammunition which contains or consists of any flechette dart, any bullet containing or carrying an explosive agent, any ballistic knife, any multiburst trigger activator, any nunchaku, any short-barreled shotgun, any short-barreled rifle, any metal knuckles, any belt buckle knife, any leaded cane, any zip gun, any shuriken, any unconventional pistol, any lipstick case knife, any cane sword, any shobi-zue, any air gauge knife, any writing pen knife, any metal military practice handgrenade or metal replica handgrenade, or any instrument or weapon of the kind commonly known as a blackjack, slungshot, billy, sandclub, sap, or sandbag.
If you wish to read more of the dangerous weapons control law, check out California.Gov PDF