Rock Steady Universal Strut Base: The universal wing strut base is a quality all metal machined aluminum base. The strut base fits any size aircraft spreader bar, bi-plane strut, or wing strut from a J-3 to a Caravan. The simple clean design straps firmly to your wing strut without using bulky blocks or bolts. The FAA friendly base can be attached quickly and easily with th Rubber Strap Kit, The Vinyl Wrap Kit, Cusioned Steel Strap Kit, or your own strap of choice. The cushioned steel strap is recommended with the Rock Steady VibeX mount and for FAA approvals. The Universal Strut Base is compatible with all Rock Steady mounts.