There's three important factors to consider when choosing a mounting solution: size, weight, and VESA pattern.Size: This is the diagonal size of your display. It's the fact your most likely to know off the top of your head, and a useful tool in finding mounting solutions that are compatible with your display. However, we strongly recommend verifying that any arm or stand you choose is compatible with both the size and weight of your monitor for maximum safety.Weight: This may be a bit harder to find out, but is almost always listed somewhere in the manual that came with your display. Manuals can usually also be accessed at the support website for your monitor's manufacturer. Be sure you're looking at the weight of the monitor without it's included stand. The original stand will need to be detached before adding an after-market mounting solution, so it's weight should not be included in determining compatible stand and mount weight limits.VESA pattern: The VESA (Video Electronics Standards Association) pattern is essentially the distance between the four mounting screws located on the back of your display. This is how you will attach your monitor to its new arm our mount. The most common sizes are 75x75 for smaller and lighter displays, and 100x100 for larger, heavier displays. Both represent the number of millimeters between each of the the four threaded holes, which are arranged in a square pattern. Some extremely large displays may use go as high as 200x200, but anything larger than 100x100 is almost always reserved for the largest big-screen TVs, not PC monitors.