This is a vqmod plugin and therefore VQMOD must be installed on your website to use this plugin
Method 1: Via FTP or File manager
To install this plugin simply place the vqmod XML file to your vqmod/xml folder of your opencart installation.
Method 2: Using VQMOD Manager
If you are using VQMOD Manager, you can click on the upload button and upload the vqmod XML file.