The 600 SXE Super Waveless Hardside Waterbed Mattress has firm support with virtually zero wave. It utilizes Sterling’s patented Progressive Rate System (PRS) which gives personalized support to each sleeper and provides extra support from mid-torso through the hips and buttocks to each sleeper. The 600SXE model has:
• A full, 9 inch depth for maximum flotation and minimum displacement between sleepers of different size
• Tethered Wave Control Systems keep the wave control/support system in place and prevent shifting of those materials
• Main seams are recessed completely underneath the mattress to eliminate flexing and stress on those seams
• A black bottom panel made from a special vinyl formulation that is better at withstanding heat from the heater