With the hottest months on the horizon, many of us are looking into gettingsummer-ready, lighter locks.

As perBellatory, Sun-In is one of the most popular highlighting products out there.

The easy-to-use spray is designed to be spritz-and-go, letting it work withsunlightor heat to naturallybleach the hair.

Blond woman at the beach

Sun-In’s bottle warns against using the hair product on dark hair, and for good reason.

Others who should avoid Sun-In’s natural bleaching?

Anyone who has dyed their hair in the last six months.

Woman on hammock in sunlight

Unless you want rainbow brights instead of buttery blond, you might want to consider avoiding the cult-classic spray.