laid on the left panel 12 and a series of overlapped checks 15 are superimposed on the record sheet 14 each check has an ink transfer strip on its reverse side for transferring information written directly on the check to the underlying record sheet 14 the checks 15 are aligned with the spaces on the record sheet 14 by means of alignment pins such as the pins 16 and 17 which protrude upwardly from the panel 11 and extend through holes in the record sheet 14 and perforated stub portions along the left hand margins of the checks 15 for the purpose of securing the record sheet 14 and checks 15 on the panel 11 and of enabling the same to be periodically replaced a clamping assembly 20 is provided as best seen in fig3 and 4 the clamping assembly 20 comprises an elongated relatively narrow clamping flange 21 which extends lengthwise of the panel 11 from top to bottom along its left hand margin the clamping flange 21 is hingedly secured to the panel 11 by an elongated hinge pin 22 which extends through interdigitated bent portions of the clamping flange 21 and the panel 11 see fig5 thus the clamping flange 21 can be pivoted about a longitudinal axis extending along the left hand edge of the panel 11 such as in the manner illustrated in fig5 preferably an ejector strip 23 having turned portions interdigitated with the clamping flange 21 and panel 11 is pivotally mounted to the hinge pin 22 for facilitating the disengagement of check stubs from the writing panel 11 as illustrated in fig5 in order to releasably secure the clamping flange 21 in clamping relation with respect.