January Jones is always "so game" to change her hair colour, according to her colourist.
The natural blonde debuted a gorgeous brunette style in Los Angeles on Monday.
Her colourist Jennifer J. says the 34-year-old is always keen to try new shades when it comes to her locks.
"We've done so many colours," Jennifer exclaimed to Us Weekly.
"She's been pink and rose gold and red and blonde and all sorts of colours. We're just going through all the different colours! [Her latest hair colour] is a great change and it was fun. We did her brows too, so it looked really pretty on her... She's just so game!"
Jennifer used a semi-permanent shade from Wella Professionals line Illumnia to achieve January's chocolate-brown shade.
Mad Men star January proved how versatile she is in June, when she stepped out with a deep copper tone in her hair.
Jennifer admires the mother-of one for her openness to try new things.
"She's so brave and she loves doing different things," she gushed.
"One time, seven or eight years ago, we made her whole head bubble gum pink! It's fun to do colour changes, especially with somebody who looks good in everything."
Beverly Hills Juan Juan Salon colourist Jennifer also works with the likes of Twilight stars Kristen Stewart and Robert Pattinson.
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