Electric plug having horizontal/vertical installation modes

An electric plug comprising:

• a front housing formed of a bottom cover shell and a top cover shell, said front housing comprising a plurality of insertion slots in the bottom cover shell thereof, and a plurality of notches in a rear side thereof;
• a rear housing formed of a bottom cover shell and a top cover shell and pivoted to said front housing, said rear housing comprising a plurality of knuckles protruded from a front side thereof and respectively pivoted to the notches of said front housing;
• a plurality of conducting blades mounted in said housing and respectively extended out of the insertion slots of said front housing in direction perpendicular to a front side of said front housing, said conducting blades each having a rear end respectively suspended in the notches of said front housing;
• and
• a plurality of metal terminals mounted in said rear housing and connected to a power cord, said metal terminals each having a front end respectively pivoted to the rear ends of said conducting blades in the notches of said front housing for enabling said rear housing to be turned relative to said front housing between a first position where said front housing and said rear housing are maintained horizontally aligned, and a second position where said front housing and said rear housing are maintained at right angles.