an end of one of the two truss assemblies 80 the other end of each truss assembly 80 abuts one of the ends of the front bar 28 the top end of each vertical support 81 abuts an end of the front bar 28 with the bottom end of each vertical support adapted for attachment to the ground or a floor of a building not shown thus the two truss assemblies 80 the header bar 22 and the front bar 28 form a rectangle with the header bar 22 and the front bar 28 parallel to each other and the two truss assemblies 80 parallel to each other each truss assembly 80 consists of two three membered simple trusses 85 with each simple truss 85 having a top bar 86 a bottom bar 87 and a stringer bar 88 attached together to form a triangle the two simple trusses 85 are attached together with the stringer bars 88 facing each other and with the top bars 86 mutually parallel to each other so that the two top bars form one long continuous member with the plane containing the truss assembly 80 normal to the ground or floor preferably the three members in each simple truss 85 are welded together and each end of truss assembly 80 is welded either to the header bar 22 or to the front bar 28 additionally the simple trusses 85 are removably attached to each other and the vertical supports 81 are removably attached to the rest of the frame reference is now made to fig1 and.