Safety Switch: A safety switch, also known as a disconnect switch or isolator switch, is a device used to disconnect the power supply from an electrical system for maintenance, repair, or other purposes. It helps ensure the safety of personnel working on the electrical system.

Non-Fusible: Indicates that the safety switch does not have fuses as part of its design. Non-fusible switches rely on other means, such as a circuit breaker, to provide overcurrent protection.

3 Poles: This refers to the number of poles in the safety switch. In this case, it has 3 poles. Each pole provides a separate disconnect for a phase of a three-phase electrical system.

100A: Indicates the ampere rating of the safety switch, which is 100 amperes. This rating specifies the maximum current the switch can handle without exceeding its design limits.

600V: Indicates the voltage rating of the safety switch, which is 600 volts. This is the maximum voltage the switch is designed to handle safely.

Nema 3R: NEMA (National Electrical Manufacturers Association) 3R is a type of enclosure rating. Nema 3R enclosures are designed for outdoor use and provide protection against rain, sleet, and ice. They are also suitable for indoor use.

The GENERAL ELECTRIC Safety Switch you've described is a non-fusible switch with 3 poles, a 100A current rating, a voltage rating of 600V, and is designed with a NEMA 3R enclosure, making it suitable for outdoor applications and providing protection against environmental conditions.