Abstract: A modular structural load bearing device including light-weight composite structural members each including an elongated body having at least one internal recess for a cable in the recess or series of recesses. Preassembled and presized composite support members and connectors can form a modular structure, such as a crane. When used, end pieces or other components on an end of the elongated body can secure a cable. For assembly of the structural load bearing apparatus, connectors can be used with composite structural members that are light-weight with relatively thin walls while providing enhanced benefits for resisting the combination of tension, compression and buckling forces.