For players using modern mouthpieces on vintage horns, it is often difficult to "pull out" far enough to get down to pitch. In this case, a "neck extension" is sometimes installed. However, this extension to the neck alters the horn and makes playing the instrument on a vintage mouthpiece no longer possible. In this case, it may be more useful to add the extension to the mouthpiece rather than the neck. Extensions can be added to Metal or Hard Rubber mouthpieces.