The vitamin c serum is only MADE BY ORDER 
To preserve the powerful antioxidants and keep the formula as active as possible. You’re getting the purest, most effective skincare, every time
 
This daily face serum combines two skin-care powerhouses, L-ascorbic acid (proven in research to be the purest, best-for-skin form of the powerful antioxidant vitamin C) and moisturizing hyaluronic acid (a hydrator that’s naturally present in the body). The unique two-part design maximizes potency and freshness, delivering a serum that stays active all the way through its use while staying paraben-free.
 
The shelf life is about 3-4 months
As soon as the serum changes colour, the vitamin C has oxidised.
 
Monique's tip  if you combine it with the active oil you get a double C combination that works wonders for pigmnetation and lighten up the skin