It is kept there against spring tension by a pawl pivoted on the frame. This was achieved by a ratchet and pawl mechanism. A spring-loaded pawl or "click" presses against the ratchet teeth, preventing the mainspring from unwinding. A later design implemented a rolling cylindrical pawl called a "nut" to retain the string. If the parking pawl breaks off or bends, serious transaxle damage can occur. Later, these click/pawl mechanisms were modified to provide a limited adjustable drag of sorts. The pawl goes over center as it is turned in the forward direction. It is highly inadvisable to use the parking pawl to stop a vehicle in motion. Hence the title "rigid pawl magazine". Thus a parking pawl was deemed redundant. Some models have a button to release the pawl and allow re-use. It consisted of Alaska, Windnbreeze, and DJ Pawl. This pawl advances only when the film is to be moved to the next image. The sect was originally named "Khuangtuaha Pawl", after the founder Khuangtuaha.