As you can see from the picture, this pair of mounts holds two 24 inch monitors. They were easy to put together. Attach to a desk or desk two ways, either with a clip that hooks on the edge or with a clip that works through the access hole as shown. Very clean design, I had a few guests in my office and immediately commented about it There are adjustments to change the tension to keep the placement in place, I didn't have to fiddle with any settings, they hold the monitors perfectly even if I change orientation or placement. Overall, these mounting brackets have been a great addition to my workspace.