Shown is a fence post system and a coupling used in such a system for coupling the fence rails and fence posts of metal tubular fences such as those used in horse and cattle ranching operations. A clamp ring is secured about the vertical tubular metal fence post. A pair of clamping body components fit about the horizontal fence rail and are secured by top and bottom tightening bosses and tightening elements. When tightened, the assembly nearly completely circumscribes the exterior surface of the fence rail, providing near 360 degree circumferential contact. The coupling can be articulated in various ways. It can be rotated about the fence post before tightening. It can also be pivoted in a vertical plane to adjust for changes in the elevation of the fence line.
