The two-section Manfrotto 196AB-2 Articulated Arm articulated arm supports 3.3 lbs @ full extension and weighs less than 1 lb. It also benefits from the extra versatility given by the sliding extension system which allows easier positioning of lighting fixtures even in awkward and tight spaces.
Maximum Length is 23.8 inches, and the bottom 5/8" spigot (compatible with the Superclamp, sold separately), also has a 1/4" thread.
Specs
Specs