IOGear GKM521R user manual From the tabs on the top, click on Button
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Mouse Configureation
3.From the tabs on the top, click on Button.
Note: Please ignore the mouse diagram shown on the left-side of this window, as this is provided as an example. To see a diagram of your specific mouse, please refer to the image “Figure 1: Mouse Buttons” where you can clearly identify buttons 3, 4, and 5.