a bracing sheet used in the display unit of fig1 fig2 is an exploded view of an alternative embodiment of bracing sheet to be used in the display unit of fig1 fig2 is a front view of an alternative embodiment of bracing sheet and fig2 is a front view of an alternative embodiment of self expanding display unit referring to the drawings and initially to fig1 to 3 thereof there is shown a display unit indicated generally by the reference numeral 1 comprising an elongate bracing sheet not shown and a pair of elongate display sheets 3 5 each having a display face 7 9 each display sheet 3 5 is divided into four panels 11 a 11 b 11 c 11 d by pairs of crease lines 13 a 13 b shown as dashed lines the crease lines 13 a 13 b are formed during the manufacture of the display unit 1 and allow the substantially rigid material used to construct the display unit to fold easily at those lines at each longitudinal edge of each display face there is provided a pair of slots 15 one slot in the uppermost panel 11 a and one in the lowermost panel 11 d each of the slots 15 in the lowermost panel 11 d engage with one of a pair of complimentary tabs 17 on the.