Or whatever they're called. Most teles have one on the headstock for the B and high E strings. But, some have 2, one for the D and G string as well. Why is that? I have an ever so slight buzz at the open G that goes away when I push down on the string behind the nut. I also have locking tuners so I can't wind the string down lower on the post. Any reason not to add another string tree?