The ET-S Glass is an upgraded version of the Aspire CE5. It has an exterior metal sleeve protecting the glass tank with two small windows that allow you to see how much liquid is left in the tank at all times.
 
Specifications:
 
Liquid Capacity - 2.0ml
Coil Type - Aspire BVC Coil
Draw Style - MTL (mouth-to-lung)
Connector - eGo (internal)
Diameter - 14mm
Airflow - Fixed
Replaceable Glass - No
Mouthpiece Material - Metal
Tank Material - Metal/Glass
Fill Method - Bottom-Fill