Level 1: Totally see-through that needs an inner to cover the neck
Level 2: See through that might need an inner to cover the neck depending on colour
level 3: Semi-through that needs double layer to cover the neck
Level 4: Almost opaque and does not need double layer to cover the neck
Level 5: Totally opaque
Disclaimer:Please bear in mind, photto taken are captured in a photography studio with bright light from all angle. The colours are made to be the most nearest possible and might vary from each computer/mobile settings.