A very light, blue-tinted hydrating serum. Sodium hyaluronate and pantothenic acid do the water-binding, with centella asiatica and mushroom extract behind them. Menthol gives the immediate cooling the name refers to, and Blue 1 is what gives the fluid its color. There are no acids and no retinol in the formula, and no percentages are published. It absorbs in seconds and leaves nothing behind.

For skin that feels tight, warm or reactive: after sun, after a facial, in air conditioning or off a flight. It layers under or over almost anything, including on top of Active Serum to take the edge off. Morning, night or both. The menthol makes it feel cold, and if that stings you, it is not your serum.