Dryer high-limit thermostat. L257-88F, L125-31C. The high-limit thermostat cuts off power to the dryer if the dryer overheats. If the dryer won't heat, the high-limit thermostat may have blown.
Dryer high limit thermostat assembly. The thermostat has reset button in center it is trips due to poor air flow such as a clogged exhaust vent.