The Manfrotto 244N Variable Friction Magic Arm differs from the
regular Magic Arm, in that the Variable Friction Arm allows partial
locking in place of a light, grip, or a camera. This comes in handy when
using a light or camera to track a subject. It is a pivot arm with a
large locking knob. One end will support a light that has a baby (5/8")
receptor. The other end is designed to fit into a Super Clamp socket, or
other 5/8" receptor.