Your specific version of Box Sync can be found on the Settings or Help tab from within the Box Sync Preferences. The Preferences window can be opened by right-clicking the Box Sync icon in your System Tray or Menu Bar and selecting Preferences.
If Box Sync is not running or if you are unable to open the Preferences window, you can also check the version by going to the following locations:
Control Panel > Programs and Features > look for Box Sync in the list of programs
Apple symbol (top left) > About This Mac > System Report > click Applications under the Software section on the left side > look for Box Sync in the list of programs