It's the date of production of lipstick. Number or color number, representing the production batch number and production date; Generally speaking, the date of production should be seen from the second number at the bottom of lipstick. The number marked above, 1-9, stands for1-September; if it is a, b and c, it stands for 10,1,12. M_A_C always pursues the integration of fashion, happiness and fantasy, and respects the rights and freedoms of people of different races, genders and ages in pursuing dreams and beauty.