Texas Penal Code Sec. 46.01
(11) "Switchblade knife" means any knife that has a blade that folds, closes, or retracts into the handle or sheath, and that:
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(B) opens or releases a blade from the handle or sheath by the force of gravity or by the application of centrifugal force.
Texas Penal Code Sec. 46.05
(a) A person commits an offense if he intentionally or knowingly possesses, manufactures, transports, repairs, or sells:
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(5) a switchblade knife;
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(e) An offense ... committed under Subsection (a)(5) ... is a Class A misdemeanor [punishable by a fine not to exceed $4000 and/or confinement in jail for a term not to exceed one year].