The Earthing Mattress Cover is made from our proprietary grounding material that is the culmination of two decades of research and development. Clint Ober designed it after feedback from our customers that they wanted a sleep option that would last longer than silver-threaded grounding sheet. The grounded Mattress Cover can be placed over or under your fitted sheet. It is thin, 100% conductive, easy to clean, and very durable. Sleeping grounded is one of the easiest ways you can ground your body consistently each day for 6-8 hours!