It's not convenient to use heat, so I want to do it Vitamin C serum, manual use, human hand, no heat, formula ascorbic acid 20% Ethoxydiglycol 20% Propylene Glycol 20% Butylene Glycol 20% Ferulic Acid 2% Vitamin B5 3% Double Hyaluron Liquid 10% 1,2 Hexanediol 3% Apple phoretin 3% Vitamin E 1% Satin ...