These control switches were once manufactured by Allis-Chalmers and Siemens and were used in many switchgear assemblies built by these companies. This particular style switch is also used in the mining equipment manufactured by Joy Mining Machinery, now known as KOMATSU. The standard 210 instrument and control switches are used in conjunction with circuit breakers, transformer tap changers, motor operated rheostats and many other types of electrically controlled apparatus. The switches are available as either maintained or spring return contact types. They are designed for panel mounting and are furnished with a choice of handles. POWERTECH electrical control switches are the BEST switches you can buy. Don't trust critical operations to flimsy control switches.