The Manfrotto Double Articulated Arm has three adjustable sections. The 396 Series of arms is more rigid that the 196 range to support heavier loads -- up to 11 lbs. Its extendable sliding arm system extends up to 34 inches in length, and features a quick lock system.
The bottom spigot is hexagonal, for a sure fit into a Bogen or Avenger Super Clamp, or a Matthew Mafer. It also has a universal adapter section for attaching to a wide range of stands, clamps and other grip equipment.