Our Kinder Reflex mattress has a 13.5 gauge open coil spring system. Designed to distribute weight away from the heaviest parts of the body, to support the sleeper. Made from hypo-allergenic materials to repel dust and other allergens for a hygienic & breathable sleep surface. Covered with a soft knit stretchy fabric, allowing persistent air circulation, to maintain freshness. Available from 3ft Single to 5ft Kingsize.