Apply Isdin Isdinceutics Hyaluronic Concentrate Serum morning and evening to clean, dry face, neck and décolleté, with a gentle massage in circular motions until completely absorbed. Apply Isdin FotoUltra Age Repair Fusion Water Fluid FPS50 on clean and dry skin, half an hour before sun exposure and as the last step of the skincare routine, before make-up if necessary. Reapply every 2 hours or whenever you sweat, swim or towel dry.