ColourPop Backseat is a cool blue with a frost finish that is permanent and retails for $4.50. In comparison, Natasha Denona Aqueous (261M) is a cool blue with a metallic finish that is limited edition and retails for $29.00.
Natasha Denona Aqueous (261M) is 90% similar — it is more shimmery, lighter, warmer.
