Add this Manfrotto Heavy Duty Boom to your light stand to give greater flexibility in lighting set ups. Arm tube diameters: 35mm.; attachment: type25 + spigot art. 013; color: black; column cross- section: round; counterweight: 44.09 lbs.; load capacity at maximum extension: 13.23 lbs.; material: aluminum; maximum extension: 110.24 in.; minimum extension: 39.37 in.; 3 section boom arm; weight: 19.62 lbs.