14 which will support up to seven tubular members with respective pins and end caps this embodiment may be used for example at the outer periphery or border of a space frame such as a geodesic dome or a truss because the ring orientation may be vertical with respect to the ground and two horizontally oriented tubular members may be attached to the longer segment of the six sided ring 14 fig1 shows another embodiment of the present invention designated as 16 as shown two rings 3 are fabricated parallel to one another with the addition of four perpendicular spacers 15 joining the two rings 3 the distance between the parallel rings 3 may be for example u00bd u2033 to 1 u2033 depending on the tube size this embodiment may be used for providing four sections for joining tubular members the assembly 16 for example may be used for tubular members having one size for attachment to the lower ring 3 and another size for attachment to the upper ring 3 this embodiment may be used for example when multiple tubular members are positioned in the same plane but need to be perpendicular to the ring plane this ring structure 16 provides additional stability in complex space frame structures the spacers 15 provide both positioning indices as well as structural support fig1 and 13 show two more embodiments of ring structures designated as 17 and 18 respectively as shown in fig1 two rings 3 are fabricated parallel to one another with the addition of eight spacers 15 providing eight sections for tube placements the ring structure may support for example eight tubes depending on the ratio of the outer tube diameter and ring diameter fig1 shows two rings 3 fabricated parallel to one another with the addition of.