549.11 CARRYING CERTAIN WEAPONS PROHIBITED.
   (a)    No person shall carry on or about his person any weapon known or designated as brass knuckles, billy, slingshot, sandbag, blackjack or other weapon of similar character, or any knife fitted with a mechanical device for automatic release of the blade, opening the knife and locking the knife in the open position, commonly known as a switch or automatic spring knife, or any knife having a blade two and one-half inches in length or longer, or any straight edge razor.
   (b)    This section does not apply to any such weapons designated for use by officers of the law, or when engaged in lawful business or pursuit justifying possession of such weapon.
   (c)    Whoever violates this section is guilty of a misdemeanor of the first degree.