... of human-engineering and mechanics;3,hollow inner structure, four air holes, good ventilation system, keep dry and clean;4,high ... 8,high quality, 20 years warranty.About Us Guangxi Hisleep Mattress Group Co., Ltd(Guangxi Shuibao) is a large and profossional ... the ONLY FACTORY in China who manufacturing unique balancing-net MATTRESS, awarded 11 National patents. Having 21 years producing experience, our ...