with the fourth side open the back face 3 may have a pair of back face vertical supports 4 running parallel to each other and to the rear legs 2 the back face vertical supports 4 may be a guide track the back face 3 may have a plurality of supports 5 attached to and extending between the back face vertical supports 4 in any desired configuration each section of the articulating mast may have a plurality of back face horizontal supports 6 each back face horizontal support 6 may be pivotally attached on one end to one of the back face vertical supports 4 and pivotally attached on the other end to one of the rear legs 2 each section of the articulating mast may also have a plurality of back face diagonal supports 7 where one end of each back face diagonal support 7 is pivotally attached to one of the back face vertical supports 4 adjacent one of the back face horizontal supports 6 the rear legs 2 may have a plurality of pin receivers 8 adjacent the back face horizontal supports 6 the end of each back face diagonal support 7 that is not pivotally attached to one of the back face vertical supports 4 may attach to one of the rear legs 2 by inserting one of a plurality of pins through the end of the back face diagonal support 7 and one of the pin receivers 8 each back face diagonal support.