I bought the eyelash serum 9 weeks and use it daily since then. Unfortunately, so far no clear change in eyelash length has occurred. My eyes still burn after application and the eyelashes approaches have slightly discolored. If you look on the Internet time after the agent, who is also present in the these eye drops, you can read that in the application of eye drops it ever came to the side effect eyelash growth only at about 50% of patients. How do M2 Beauté therefore argue that the serum acts at each and thus justify the price? From me, therefore no recommendation to buy.