Classic eyelash extensions are placed one extension at a time on individual lashes, creating fuller, longer, and more natural-looking eyelashes. "Classic" is referring to the most natural form of lash extensions you can start with & is recommended for your first time with eyelash extensions. The duration of the session can be anywhere from 1 to 2 hours depending on your natural eyelashes. Time is taken to make sure you're getting the quality work required to retain your lashes and look good.