Amber thanks f(x) fans for sticking with them over the past 4 years

f(x) celebrated their 4th anniversary today, and Amber took to Twitter to thank all her fans!

She tweeted a photo of the girls holding each other's wrists, and wrote, "#4yearswithfx Time really flies by. Thanks for being with us all these years!".

SEE ALSO: f(x) conclude their 'Rum Pum Pum Pum' promotions

f(x) recently concluded their "Rum Pum Pum Pum" promotions. During the promotions, the girls won various trophies from music shows and swept music charts immediately upon release, ending up at #1 on the Melon Chart for the month of August.

Congratulations to both f(x) and their fans!