The 66L040 is a RoHS-compliant, subminiature bimetallic thermostat in an 8-pin DIP package designed for accurate temperature sensing and switching in a single device. It features gold-plated contacts, positive snap action operation, and can be configured for either close-on-rise (make) or open-on-rise (break) contact operation. The thermostat operates over a temperature range of 40°C to 130°C with a standard tolerance of ±5°C, achieves contact ratings up to 1.0 A at 48 VDC or 120 VAC, and supports low-level switching down to 0.001 A at 5 VDC with up to 100,000 life cycles. Its compact size and sealed epoxy construction make it ideal for surface and air sensing on crowded PC boards, and it is suitable for auto-insertion equipment and wave soldering operations. Typical applications include computers and peripherals, aircraft, automotive systems, and test equipment, where it can control indicator lights, audible alarms, display messages, or system shutdown functions.