PURPOSE: To eliminate a fear of losing a sheet which places information to be desirably preserved by mounting an implement for binding the sheets in which two holes are punched and a thin punch for punching two holes at the sheet on the inner surface of a front cover.

CONSTITUTION: When a facsimile FAX is, for example, received and its reception sheet is preserved, the sheet which places information to be desirably preserved is inserted into the sheet retainer 9 of a board 10 of a thin punch 4 mounted on a front cover 3, an operating plate 13 is rotated inward at a rotary shaft 18 as a center, and two holes are punched at the sheets by engaging a protruding cutter 12 with a hole receiving cutter 8. The two holes of the sheets are inserted to two pieces 5 of a binding implement 2, pressed by a sheet retainer 14, and fixed by a fixing slider 15. Thus, the sheet which places the information to be desirably preserved can be bound at a binding implement 2 without losing it.