The InnoMax Genesis 600 Balanced Motion Waterbed Mattress reduces motion to provide custom tailored Hydrodynamic Sleep, resulting in virtually perfect ear to ankle body alignment as defined by physicians and chiropractors for the ideal sleeping posture. This deep fill InnoMax waterbed mattress, for use with minimum 9x72x84" rigid box or wood waterbed frames, performs best when fill level is below the top of the Safety Liner. The G600 Waterbed Mattress, which provides Full Depth Flotation and Balanced Motion Performance, also includes a mid-body wave reduction system balanced between free flow and wave less performance. Other features include 22 Mil Premium Vinyl, Contouring Body Profile Low Tension Sleep Surface, 2" Double Reinforced Corners, 4-Way Tethered Support System, Recessed L-Seam Construction and a Thermally Efficient Black Bottom. The SG1 (Specific Gravity 1) Low Tension Mattress (LTM) surface features responsive levels of support for your body’s varied levels of need; for the head, mid-body spinal and leg areas. For near perfect body alignment, the responsive give of the generously overcut SG1 surface cradles your body while the interior elements provide complementary support. Additionally, the SG1 LTM surface eliminates disruption of the other sleeper when one gets out of bed and with varying weights of sleep partners. NASA astronaut training is often done under water as it simulates the effects of being weightless because the human body, comprised of 90-percent water, is in balance with the fluid environment. Just as babies are suspended in a gravity neutral fluid environment until born, InnoMax SG1 Hydrodynamic Sleep mattresses truly offer flotation support as nature prescribes. The body can only be truly relaxed when muscles do not have to constantly fight the forces of gravity. SG1 fluid suspension evenly supports your body in gravity neutral sleep and offer hygienic environment as they are easily cleaned with approved Waterbed Vinyl Conditioner.