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1. A tamper resistant fastener system for one way installation of a fastener, comprising:
a fastener defining a longitudinal axis and having a head and a threaded portion defining a plurality of threads, said head having a plurality of angularly spaced apart fastener teeth extending around the outer periphery of said head remote from said longitudinal axis at a greater distance than said threads, each of said fastener teeth having a vertical engagement wall extending substantially parallel to said longitudinal axis and a non-vertical disengagement surface; and a torque transmitting drive tool (having a head and a socket) for driving said fastener, said torque transmitting drive tool having a drive end and a wrench attachment end, said drive tool further having a plurality of drive tool teeth formed at said drive end for engaging said vertical engagement walls of said engagement teeth, whereby on application of torque in a first direction said drive tool teeth engage said fastener engagement teeth and advance said threads, and whereby application of torque with said drive tool in an opposed direction causes said drive teeth to contact said non-vertical disengagement surfaces and is not effective to turn said threads so as to to remove said fastener.
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