A variable optic attenuator is embodied in the form of a plug type connector carrying a first fiber for selectively mating with a socket type connector carrying a second fiber with a distance separating the fibers for attenuating optic signals passing therethrough. The attenuator includes a tubular body to be coupled to the socket connector with a front end. A double screw mechanism carrying the first fiber is attached to a rear end of the body with the first fiber extending through the body to axially align with the second fiber of the socket connector. The double screw mechanism includes a connecting nut attached to the rear end of the body and defining an inner-threaded bore. A tubular knob has external threading of first screw pitch and inner threading of second screw pitch different from the first pitch. The external threading of the tubular knob engages the inner threaded bore of the connecting member. An elongate rod defining a central bore for receiving and retaining the first fiber is received in the tubular knob. The rod has external threading mating the inner threading of the knob whereby rotating the knob induces different linear displacements of the knob and the rod, dependent upon the screw pitches, in opposite directions. The first fiber is thus moved a displacement corresponding to the difference of the displacements of the knob and the rod.