Our underarm whitening serum contains glutathione and niacinamide. It can deeply moisturize the skin, provide long-lasting hydration effects, effectively lighten dullness, with a refreshing texture giving you a brand new experience. Its usage method is very simple: 1. Clean and dry the armpit skin. 2. Take an appropriate amount and apply evenly on the armpits. 3. Gently massage until absorbed. And it can lighten dullness, even out underarm skin tone, making the skin fairer and softer.