How long does one ampoule of the M2 Eyebrow Renewing Serum (BRS) last?
This varies greatly depending on the size of the application area.
https://www.m2beaute.com/en/eye-care-faqs/eyebrow-serum-faq-eyebrow-renewing-serum/how-long-does-one-ampoule-of-the-m2-eyebrow-renewing-serum-brs-last