LiteFuze LC-300US 300Watt Step Up/Down Travel Voltage Converter, US Cord Max Up to 300 Watt capacity with Thermal Fuse Protection; Voltage Step Up or Step Down functionality for World Wide Use Fully Grounded Transformer from Input to Output for safe operation Converting box Technology - No Noise, Light Weight, Energy Efficient Product Dimensions: 5 x 3.5 x 3 inches ; 2 pounds Please select switch 115V if you are using it in the USA and Make sure you switch to 230V if you are using it overseas countries The efficiency factor of this transformer is 2.0. Do NOT exceed 150W when using continuously. The transformer is equipped with thermal fuse protection and will shut off when overloaded. It will turn on once it cools down again