SIMPLE USE: Once the patented SmartShelf design detects your cold meal, it automatically begins the heating cycle on any flat-bottom sealed container HEAT, COOK, WARM: Maintains a safe temperature, keeping your food hot for several hours. The perfect addition to any breakroom FULLY AUTOMATIC: No more waiting in line for the microwave; simply place your container on any shelf. Shelves work independently to perfectly heat each individual meal USER FRIENDLY: Works with any flat bottom, sealed lid container; glass, metal, dishwasher-safe plastic, or paperboard. No buttons, dials, or guesswork for cook times needed EFFICIENT DESIGN: Save breakroom space and wait with its compact and multiple-shelf design. Hot Logic SmartShelf ovens can be stacked up to three high. Units operate on a single 120V amp outlet