This unbelievable mattress is our most luxurious. In addition to all of the benefits of our Starlight Support mattress, the Starlight Support Supreme has an additional layer of plushness. The infant side remains standard with the high density extra firm foam found in our Starlight Support mattress, but the firm foam toddler side is layered with a viscoelastic memory foam. Viscoelastic foam, originally designed by NASA, now can be found in premium toddler and youth mattresses everywhere with Moonlight Slumber. The Starlight Support Supreme memory foam mattress is hypoallergenic, antimicrobially treated, and open flame resistant. It provides your older baby (9+ months), with the ultimate sleep comfort by conforming to your childs contours, supporting their growing joints, and keeping their spine in perfect alignment. For the ultimate in comfort, look to the Starlight Support Supreme.