EA56: 22x11cm. Size of a tri folded A4
C56: 22.9x11.4cm. Large enough for multiple trifolded A4 or, one tri folded A4 and an extra (EA56) envelope
C5: 22.9x16.2cm. Large enough for multiple single fold A4 paper or, one single fold A4 and an extra (EA5) envelope
C6: 16.2x11.4cm. For the standard greeting card sizes
_As a reference: A4 paper is 21x29.7cm (normal print paper)_