This Nocturnal Lights Aluminum Double Section Ball-Joint Arm Combo includes two 12" (30.48cm) double ball-joint arm sections and 3 ball-joint clamps. Use the bottom clamp to attach the arm to a ball on your housing or housing adapter, and the top clamp to a ball joint adapter on a Nocturnal Lights light. The third clamp is used to attach the 2 arm sections together.
The arm is constructed from light but sturdy anodized aluminum. The 1" ball has an o-ring; this helps the clamp to hold the section in position without slipping.