PURPOSE: To obtain an easily portable page dip that can be used for any of a large booklet and a small booklet by adjusting a continuous-length material in length so that it cannot partially hang outside without replacing the continuous-length material by another one having a different length.

CONSTITUTION: A fastening groove 3 for a continuous-length material 2 is formed in a mounting tool 1 that is formed so as to detachably damp a part of a booklet. The continuous-length material 2 is fastened at an appropriate position by the fastening groove 3. The continuous-length material 2 is held so as to partially slack, whereby the length of the continuous-length material 2 can be changed.