Horizontal chambers encapsulate gel with foam beads to conform to the patient's body/ Standard foam top layer for comfort and support/ Lighter than other overlays for ease of handling/ Nylon top cover with skid-resistant vinyl bottom cover/ Fluid-proof cover/ Sturdy elastic straps secure corners of overlay to a mattress/ Dimensions: 34 x 76 x 3" (86 x 193 cm x 8 cm)