Alfaparf Milano Keratin Therapy Lisse Design Leave-In Keratin Serum Refill (125ml) is a silky, lightweight fluid which recharges every hair type with Keratin and Collagen following smoothing and anti-frizz treatments with Keratin, leaving it protected, smooth, tamed and defined. Part of the new and improved range from Alfaparf Milano, this serum is perfect for the aftercare of professional Keratin treatments, helping to counteract the natural drying process.