... ;Standard 3U-21 racks and Easy PlugTM technique are incorporated;EN 50155-compliant,etc.3. Function and Structure Characteristics ... ALSTOM;Standard 3U-21 racks and Easy PlugTM technique are incorporated;EN 50155-compliant,etc.4. Functions and structure characteristics ... ;Standard 6U-21 racks and Easy PlugTM technique are incorporated;EN 50155-compliant,etc.5. Functions and structure characteristics ...