This is not legal advice and only an interpretation of the law listed below.
As I read your state laws, it looks like they would not allow expandable batons to be carried. The law listed below lists the following; blackjack, slungshot, billy, sand-club and sandbag. The blackjack and billy are very similar devices and an expandable baton would likely carry the same punishment.
I am not a lawyer and would suggest contacting one if you wish to carry such a device in the state of Nevada. You can also just stay on the side of caution and not carry an expandable baton at all.
NEVADA REVISED STATUTES CHAPTER 202 - CRIMES AGAINST PUBLIC HEALTH AND SAFETY
GENERAL PROVISIONS NRS 202.350 Manufacture, importation, possession or use of dangerous weapon or silencer; carrying concealed weapon without permit; penalties; issuance of permit to carry concealed weapon; exceptions. 1. Except as otherwise provided in this section and NRS 202.355 and 202.3653 to 202.369, inclusive, a person within this State shall not: (a) Manufacture or cause to be manufactured, or import into the State, or keep, offer or expose for sale, or give, lend or possess any knife which is made an integral part of a belt buckle or any instrument or weapon of the kind commonly known as a switchblade knife, blackjack, slungshot, billy, sand-club, sandbag or metal knuckles;
