Hello everyone. I finally uploaded my Butter London Slapper comparison pictures :)
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Sally Hansen- Fairy Teal (2 coats)
Milani- Fresh Teal (3 coats)
Butter London- Slapper (2 coats)
Sally Hansen- Mint Sprint (2 coats)
^ With flash
^ Under lamp
^ Under lamp
^ With flash
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^ Slapper and Fresh Teal are the most similar
Fresh Teal is a little darker and more on the blue side and Slapper is more on the green side.
Thanks for reading :)