When you paste your own code into a custom HTML template, Benchmark Email sends that code as is. There are a few exceptions listed below, as well as what to expect will stay in the template, regardless of the code you use:
Benchmark Email removes:
Anything outside the <HTML> tags.
URL that are converted to tracking URLs.
Junk code from Microsoft word and other programs.
Benchmark Email keeps:
The Benchmark Email header, which often includes the permission message and link to the Web version of your email. This all stays at the top of your email.
Templates & Editor 