All CAP+ Rig System Cross-members are 7-gauge steel, and are designed specifically for mounting to uprights with 1/2” holes. They can be used with all CAP+ upright post. Depending on your personal training preferences and the available space in your facility, you can choose between single and double bars, 43" and 70" lengths, and "fat" (2" OD) and "skinny" (1.25" OD) styles with a weight capacity of 500 lbs.