To install and use Enverter for SolidWorks you will need:
1. 64 bit SolidWorks
2. Internet connection while you use Enverter (Its a cloud based Unit Converter)
To install, simply run the setup. Follow the instructions of the installer. After the setup is complete, start SolidWorks and you will see 'Enverter for SolidWorks' icon in the task-pane on the right as seen in the image below:
That's it. You can start using the Enverter.