When XrayVision (XV) is launched for the first time on a workstation, the user has the option to specify the size (large or small) of icons on the toolbar and toolbox.

To change the size of icons in the toolbar and/or toolbox:
Select Window > Control Window from the menu. The options to Use Small Toolbar and Use Small Toolbox may or may not be enabled.

Click on the desired option to change the size of the toolbar or toolbox. (Unchecking an option will make the icons larger.)