Compatible with LX Pro Arms: Upgrade your LX Pro desk monitor arm with 5-inch pole to a dual setup with this expansion kit and the Dual Side-by-Side Collar (98-745-290); use this kit to expand your 12-inch pole LX Pro desk arm to a Dual Stacking arm or use one or two Dual Side-by-Side Collar to create a triple or quadruple monitor solution Easy installation: Includes LX Pro arm, extension, monitor pivot, pole collar, attachment hardware; attaches anywhere to the pole of the LX desk mount base to hold additional monitors or installs in the Dual Side-by-Side Collar (98-745-290) Boosts productivity: Create a flexible yet stable two, three or four-monitor workstation to dramatically increase workflow efficiency; ideal solution for gaming, call centers, industrial spaces or finance where screen space is essential Broad compatibility: Fits single screens up to 34 inches diagonal and 4 to 22 pounds; compatible with VESA patterns 75x75mm and 100x100mm; easily raise your monitor up to 18.3 inches above your worksurface with 13 inches of lift; find your best view for each project with up to 360 degrees of rotation and 85 degrees of tilt Built to last: Extensive quality testing ensures your display stays stable and secure; Ergotron products set the standard for quality with a 10-year warranty and expert technical support  Upgrade an LX Pro Monitor Arm to a stable multi-monitor solution for two, three or four monitors. This kit easily attaches directly to the pole of the desk mount base or the Dual Side-by-Side Collar to hold additional monitors or a laptop computer for gaming, call centers, industrial spaces or finance applications. For triple or quadruple monitor set-ups, use with the LX Pro Large Base.