These picks, such as the common snake rake, are designed to "rake" pins by rapidly sliding the pick past all the pins, repeatedly, to bounce the pins until they reach the shear line. This method requires much less skill than picking pins individually and generally works well on cheaper locks. Advanced rakes are available which are shaped to mimic various pin height key positions and are considerably easier to use than traditional rakes. Such rakes are typically machined from a template of common key configurations since not all permutations of pin heights for adjacent pins are possible given the process by which keys are manufactured.