Kate Hudson, Zoe Saldana, Dakota Fanning, Katy Perry, Mindy Kaling, Michelle Monaghan and several others are stripping down to their skivvies to raise funds for breast cancer. They are all taking part in a social media campaign launched by Kit Undergarments, brainchild of stylists Jamie Mizrahi and Simone Harouche.

For every purchase made this month, the brand will donate 5% of sales to the Women’s Cancer Research Fund. For every post of a person in their line of underwear with the hashtag #kitstokickcancer, they’ll donate $1. The Women’s Cancer Research Fund supports research, education and outreach for the development of more effective approaches to the early diagnosis, treatment and prevention of women’s cancers.