Monitor Arms Accessories — Top 5 Questions & Answers

VESA (Video Electronics Standards Association) defines a standard pattern of four mounting holes on the back of monitors — the most common patterns are 75×75mm (for 22–24 inch screens) and 100×100mm (for most 24–32 inch commercial monitors). Before purchasing a monitor arm, look up your monitor's VESA pattern in its product specifications (found on the manufacturer's website or the owner's manual). Confirm the arm you're purchasing supports that pattern. Most commercial monitor arms support both 75×75mm and 100×100mm patterns. Some large displays (32+ inches) use 200×200mm patterns requiring specialized mounts. If a monitor uses a proprietary stand attachment with no standard VESA pattern, a standard monitor arm cannot be used.

Clamp-mount arms attach to the desk edge by clamping to the desk surface thickness — no holes required, compatible with desks 3/4" to 3–4" thick, and easily repositioned or removed. This is the right choice for rented spaces, temporary setups, and desks that cannot be drilled. Grommet-mount arms pass through a pre-drilled or existing 2–3.5 inch hole in the desk surface, secured from underneath with a nut — this provides a more secure, stable connection and is preferred for heavy dual-monitor arms and sit-stand desks where the movement cycle adds lateral stress on the mount. For permanent commercial installations with pre-drilled grommet holes (common on commercial desks), grommet mount is the more stable choice.

The ergonomic standard is to position the top of the screen at eye level or very slightly below — this places the center of the screen at approximately 15–20 degrees below the horizontal line of sight, which is the natural resting gaze angle for relaxed eyes. The viewing distance should be 20–40 inches (arm's length is the common approximation). The screen should be tilted very slightly upward, approximately 5–10 degrees, to match the downward gaze angle. On a sit-stand desk, the monitor must be adjusted each time the desk height changes — gas-spring arms allow one-finger repositioning and are essential for this use case. A monitor arm's height range of 16+ inches is recommended for sit-stand desk users.

A dual monitor arm holds two screens on a single mounting point — both monitors share one clamp or grommet. Side-by-side dual arms position both screens at the same height; stacked configurations place one screen above the other. For most commercial workstations, a side-by-side dual arm with a gas-spring mechanism provides the easiest repositioning for both screens simultaneously. Verify the arm's weight capacity — dual arms must support the combined weight of both monitors, which can total 30–50 lbs for two 27-inch displays. Also verify that the arm's horizontal reach positions each monitor's center at the user's left and right eye positions without requiring excessive neck rotation — each screen should be no more than 30–35 degrees from the user's center line.

A keyboard tray is needed when the desk surface is too high for neutral forearm position (forearms parallel to the floor, wrists straight). For desks at the standard 29–30 inch height, most users between 5'4" and 6'0" can achieve a reasonably neutral typing position without a tray. Shorter users and those on 30-inch desks typically benefit from a keyboard tray that lowers the typing surface 3–6 inches below the desk surface. The tray should articulate (adjust in height, fore/aft, and lateral position), have negative tilt capability (-15° to +15°), and include an integrated mouse platform (specify 26–30 inch wide trays). On sit-stand desks, specify a tray with a parking or swing-away position that folds flat when the desk is raised to standing height.