How to send XML from NFE consuming SEFAZ webservice

Recently colleague Rafael Corazzi posted a routine to send the XML consuming Sefaz webservice .

At one point in the routine, it instantiates a class:

SefazWebRequest request = new SefazWebRequest();

I'm using this example in my project, and I'd like to know where this class is set, or how to reference it in my project.

Thank you!