A folding mechanism comprising a first support; a second support pivotably coupled to the first support; an actuator operable to pivot said second support relative to said first support about a first pivot axis between a deployed position and a folded position; and an elongate support strut extending between said first and second supports, the support strut being adapted to permit movement of said second support about said first pivot axis when the support strut is in a first state, the support strut being adapted to retain said second support in said deployed position when the support strut in a second state; the support strut being coupled to the actuator such that the support strut is reconfigured between its first and second states as the actuator is operated to pivot the second support between its folded and deployed positions, characterised in that the support strut comprises a first member pivotally coupled to the first support at a second pivot axis; and a second member pivotally coupled to the second support at a third pivot axis; the first and second member of the support strut being pivotally coupled together for relative movement about a fourth pivot axis; the distance between first pivot axis and the second pivot axis being equal to the distance between the second pivot axis and the fourth pivot axis, the distance between the first pivot axis and the third pivot axis being equal to the distance between the fourth pivot axis and the third pivot axis; the fourth pivot axis being coincident with the first pivot axis when the support strut is in its first state; the fourth pivot being spaced from the first pivot axis, the first and second supports and first and second members of the support strut defining between them a kite quadrilateral, when the support strut is in its second state. a first support; a second support pivotably coupled to the first support; an actuator operable to pivot said second support relative to said first support about a first pivot axis between a deployed position and a folded position; and an elongate support strut extending between said first and second supports, the support strut being adapted to permit movement of said second support about said first pivot axis when the support strut is in a first state, the support strut being adapted to retain said second support in said deployed position when the support strut in a second state; the support strut being coupled to the actuator such that the support strut is reconfigured between its first and second states as the actuator is operated to pivot the second support between its folded and deployed positions, characterised in that the support strut comprises a first member pivotally coupled to the first support at a second pivot axis; and a second member pivotally coupled to the second support at a third pivot axis; the first and second member of the support strut being pivotally coupled together for relative movement about a fourth pivot axis; the distance between first pivot axis and the second pivot axis being equal to the distance between the second pivot axis and the fourth pivot axis, the distance between the first pivot axis and the third pivot axis being equal to the distance between the fourth pivot axis and the third pivot axis; the fourth pivot axis being coincident with the first pivot axis when the support strut is in its first state; the fourth pivot being spaced from the first pivot axis, the first and second supports and first and second members of the support strut defining between them a kite quadrilateral, when the support strut is in its second state.