The so-called anti-theft screw, also known as anti demolition, screw, is a kind of in order to prevent long-term placed in outdoor public environment of the fixed installation of the fastener. In accordance with the general category structure and is divided into can be mounted removable and non removable type two, the former is further divided into five angular theftproof screw, plum anti-theft screw, Y type anti-theft screws, triangle anti-theft screw, inner triangle anti-theft screw, two anti-theft screw, eccentric hole anti-theft screw, multi tooth variety structure.