This extension is for Indian users on Airtel Broadband. It will display current usage of you broadband cap. You can set refresh intervals on which your data usage will be fetched.
Please note that this works “only” if you are on Airtel Broadband (not 3G or 4G) in India. This is NOT an official Airtel extension and I’am NOT linked to Airtel, apart from the fact that I’am an Airtel BB user 🙂