A multifunctional pen often has a ballpoint pen as its main writing instrument and a mechanical pencil or highlighter for its second setting. Certain pens may have all three options available instead of two. The most common way to change between each writing instrument is to twist the barrel, which is located on the top where the clip is. You can twist in one direction to use the pen and turn backwards to use the second setting. It will not turn 360-degrees in most cases.