100% Fully functional!!! TWO MONITORS AT ONCE: Fits most 17''- 27'' Monitors with the load from 4.4 -19.8 lbs (2-9KG) for each monitor, VESA compliant patterns 75x75mm or 100x100mm; While the whole VESA Plate of this product is 118*118mm,Pls pay special attention to the size of VESA Plate if your monitor are curved monitor, Or your VESA hole is inside a recession area. FULLY ADJUSTABLE RANGE: Your two screens will have 360° rotation, tilt angle +85° to -30°, swivel ±90° Upright up to 10"(260mm) and max extension is 20.8"(530mm). Both arms of the desk mount can be easily adjusted anyway you would like. ERGONOMICS: Improve your overall well being by creating most comfortable viewing angle for work or gaming- Enjoy the freedom to adjust your monitor height and angle: Your spine, neck and shoulder will be thankful DESK CLAMP OR GROMMET: You can choose one of two available ways of installation – C-Clamp or Grommet mount. The diameter of the hole in your desk must be 0.39-1.97 inch,Desk thickness must be within 3.54 inch, easy installation, Install In 10 Min or Less. Kindly noted: Pls DON'T adjust the tension screw without the monitor mounted on it , Adjust method: If the monitor keep rising up, Pls reduce the tension screw (to the direction of "-") On the contrary, Turn to "+", Many circles needed!