Stop member includes: a first member including a first insert to be inserted into a slider via a rear mouth of the slider, and a first base positioned rearward of the first insert; and a second member including a second insert to be inserted into the slider via a slit extending between the rear mouth and a front mouth of the slider, and a second base to be overlaid onto the first base. The first and second bases are configured to effect magnetic attraction and/or repulsion between the first and second bases when the first and second bases are overlaid. The second base rotates relative to the first base in accordance with the magnetic attraction and/or repulsion to allow the second insert to pivot toward the slit.