No person shall have in his possession, wear under his clothing or conceal about his person, or display in a threatening manner, any knife commonly called “switchblade” having the appearance of a pocket knife, the blade of which can be opened by a flick of a button, pressure on the handle or other mechanical device. Such knife is hereby declared to be a dangerous and deadly weapon and shall be subject to forfeiture to the City as provided in Section 545.15
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