This 12.5" Edge B30 plush mattress features extra firm quilting and support layers that provide comfort and support, high density polyfoam support layer, the Thermocool technology, and Quantum edge steel perimter outperforms foam encasement. This mattress will bring all the support and comfort you need to get a good night sleep and with extra supportive coils around the perimeter edge, the Quantum Coils in The Edge series provide a firmer and more supportive edge that prevents the all too common "rolling out of bed feeling" that many budget mattresses exhibit. Quantum Edge Steel Perimeter bends and average of 24% more easily than foam encasement, which means less wear and tear on moving parts and a more “friendly” performance on adjustable bedbases.