The deluxe reflex plus coil mattress combines a traditional open coil spring unit with an innovative reflex foam layer for a sleeping surface that prioritizes your comfort and support the coil spring unit offers maximum spinal support as well as reducing the possibility of roll over something especially useful if you share a mattressthe use of a reflex foam layer helps with heat regulation and its hypoallergenic fillings make this mattress ideal for allergy sufferersdimensionssmall single