P.C. Sec. 46.05 -
(a) A person commits an offense if the person intentionally or knowingly possesses, manufactures, transports, repairs, or sells:
(1) an explosive weapon;
(2) a machine gun;
(3) a short-
(4) a firearm silencer;
(5) a switchblade knife;
(8) a chemical dispensing device;
(9) a zip gun; or
(10) a tire deflation device.
(b) It is a defense to prosecution under this section that the actor's conduct was incidental to the performance of official duty by the armed forces or national guard, a governmental law enforcement agency, or a correctional facility.
(c) It is a defense to prosecution under this section that the actor's possession was pursuant to registration pursuant to the National Firearms Act, as amended.
(d) It is an affirmative defense to prosecution under this section that the actor's conduct:
(1) was incidental to dealing with a switchblade knife, springblade knife, short-
(2) was incidental to dealing with armor-
(3) was incidental to dealing with a tire deflation device solely for the purpose of making the device available to an organization, agency, or institution listed in Subsection (b).
(e) An offense under Subsection (a)(1), (2), (3), (4), (7), (8), or (9) is a felony of the third degree. An offense under Subsection (a)(10) is a state jail felony. An offense under Subsection (a)(5) or (6) is a Class A misdemeanor.
(f) It is a defense to prosecution under this section for the possession of a chemical dispensing device that the actor is a security officer and has received training on the use of the chemical dispensing device by a training program that is:
(1) provided by the Commission on Law Enforcement Officer Standards and Education; or
(2) approved for the purposes described by this subsection by the Texas Private Security Board of the Department of Public Safety.
(g) In Subsection (f), "security officer" means a commissioned security officer as defined by Section 1702.002, Occupations Code, or a noncommissioned security officer registered under Section 1702.221, Occupations Code.