Make every night's sleep your best with our signature, deep-quilt-top mattress and shock-absorber box spring by Simmons. Flameguard fabric protects you while you slumber, and specially engineered foam and comfort layers relieve stress on pressure points. Innerspring design of box spring features extra coils for optimal support. Full (not prorated) ten-year warranty on both mattress and box spring. Noble Bed mattress (12" deep) and box spring (9" deep) measure 21" total depth; 12" deep mattress accommodates most sheet sets yet offers all the comfort you'll ever desire.