I want to make my own midpipe using the guide found in the How-To sticky. For quick reference, here's the link to the guide. Anyway, I need to know a few things that weren't included in the guide and the author's not responding to emails.

1. What filter is being used in the guide and where can I get it? I think it's a K&N cone filter but I don't know where to get it.
2. What size brass barb adapter is best suited for the job?

~THT