Hum, Dazco must be sleeping late -
TORs are the Triumph Off Road "mufflers" which come in either short or long. They are designated "of road" because they don't meet some street legal standards in some locations but they are universally used as upgrades here in the US. The short TORs are known for enhancing performance and are the least expensive upgrade pipe out there.
I've learned all of this from reading the posting of others as I'm also a newbie.
Others can explain better the pro's and con's as well as the tune changes required if you go that route.
Welcome to the forum - glad to see new members.
"Do what you can, with what you have, where you are." - Franklin Delano Roosevelt