The 90 Degree Gusset is part of our S3 Ecosystem and works perfectly with the Tilerunner, S3 Tube, and all the other components in the S3 Ecosystem. The 90 Degree Gusset provides support for two tubes, 90 degrees from each other. The 90 Degree Gusset has additional holes that allow for mounting an S3 Tube at a 45 degree angle.Specifications: