Product details:

This boom attaches to the shaft of most light stands and gives more lighting possibilities. Great for product photography or holding a hair light. Designed for stands with diameters of 19, 20, 25, 28mm. 25mm. This arm complete with Pivoting Clamp 124, Counter Weight 023, cable clips and locking key. Arm tube diameters 25mm. attachment type25 + spigot art. 013 color black counterweight 9.48 lbs. load capacity at maximum extension 6.61 lbs. material aluminum maximum extension 78.74 in. minimum extension 27.95 in. 3 sections weight 12.57 lbs.