To operate a lever of a supplement marker, interlocking with the reciprocating movement of a slider without using a spring for returning the lever.

A merchandise supplement indicator 1 includes a slider 4 provided in the interior of a merchandise case 3 to freely reciprocate, and a cartridge 2 in which the slider 4 is energized by a spring 5 includes: a visible window 6 formed on the front of the merchandise case 3; a seesaw type lever 8 pivotally supported on the bottom of the merchandise case 3 by a fulcrum pin 7; a supplement marker 9 corresponding to the visible window at the forward end of the lever 8; a cam 10 for indicating position displacement formed at the position to come into contact with the slider 4 in the forward movement of the slider 4; and a cam 11 for return position displacement formed to come into contact with the slider 4 in the backward movement of the slider 4.