[en] A support member for superconducting magnets and other cryogenic devices has been designed, fabricated and structurally and thermally evaluated. The member is a cylindrical post constructed with fiber reinforced plastic (FRP) tubing and having metallic heat intercepts and end connections. All FRP to metal connections are made by mechanical shrink fitting and do not employ adhesives or fasteners. The post can operate in tension, compression and flexure or in combinations of these loads. The details of the design and construction are enumerated. Structural performance has been measured in tension and compression at 80 and 300 K and in flexure at 300 K. Creep effects on the shrink fit joint reliability are being evaluated. Thermal performance has been measured for a post with ends at 4.5 and 300 K and with heat intercepts at 10 and 80 K. The measured performance has been compared with the analytical predictions. Full scale, working, prototype posts have been successfully utilized in several model cryostats for the Superconducting Super Collider dipole magnet development program