. . . [E]very person, firm or corporation who within the State of California knowingly possesses or transports any form of shell, cartridge, or bomb containing or capable of emitting tear gas, or any weapon designed for the use of such shell, cartridge or bomb, except as permitted under the provisions of this act, shall be guilty of a public offense and upon conviction thereof shall by punished by imprisonment in the State Prison not to exceed two years or by a fine not to exceed § 2,000 or by both such fine and imprisonment . . . (exceptions for police and definitions).