Tamper-resistant electrical wiring device system

A tamper resistant (TR) mechanism for use in a receptacle is disclosed. The TR mechanism movable between a first or blocking position and a second position wherein a two-bladed plug with a ground pin may contact the underlining conductive terminals so that electricity can flow to the electrical plug. The TR mechanism may include first and second sliders for blocking the openings formed in the receptacle, first and second locking tabs, and a ground pin slider partially located with a ground plug opening formed in the receptacle. In use, inserting the ground pin causes the ground pin slider to move to a second ground pin slider position, which causes the first and second locking tabs to align with a stem portion of the ground pin slider. Thereafter, contacting the first and second sliders with the two-bladed plug causes the first and second sliders to move to their second position.