TIRTIR SOS Serum is the ultimate hydration boost your skin craves. It's enriched with Polyglutamic acid(PGA). PGA has a x10 greater water-holding capacity than hyaluronic acid. It can bind and retain moisture more effectively. TIRTIR SOS Serum delivers unparalleled, deep, and enduring hydration, leaving your skin glow, rejuvenated and plump.