Tool free installation. mouse pad can be clamped on your desk in seconds with No DAMAGE TO YOUR DESK. No need to drill holes in your desk. Position your mouse under desk shelf ; essentially expand space for holding a million different things such as your speaker, phone, mouse or tablet. Ergonomic mouse tray keeps you in correct body postures for working or reading on computer screen; prevent shoulder, back, and wrist pain and injury from bad postures. You can clip it on your desk between 0.65 inch and 1.5 inch thickness, and can be easily installed for either right or left hand users. We DO NOT recommend using on table with edge slope and edge with decorative strip or glass office table. Rotates under the desk and store when not in use. Buy 2 to make one keyboard tray. Weight: 1.2 lbs/pcs colour:Black material:plastic size:25*19.5cm Package Contents: 5*Mouse tray Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.