Works with most 110 and many 220-volt plugs. Outward/inward rotation allows for easier application & storage. Surrounds the electrical plug and protects against accidental reconnection. Patented rotating design allows for easier installation in confined space applications. Complete with high-visibilty permanent safety labels (English, French & Spanish). Tough, lightweight, dielectric Zenex thermoplastic bodies withstands chemicals. Performs effectively in extreme conditions (temperature range -50°F (-46°C) to +350°F (177°C)).