A piton is a metal spike, wedge, or peg that is driven into a rock or ice surface as a support for a mountain climber. It is used in big wall climbing and in aid climbing as an anchor for protecting the climber against the consequences of falling. Pitons are sized and manufactured to fit a wide range of cracks, and they come in different types, including beak, knifeblade, and lost arrow. Pitons are still found in place as "fixed" pitons on some established free climbing routes, as fixed belay station anchors, and in places where nuts or cams do not work.