Our Beach Electric Wheelchair equips with Synchro moving gradienter equipment patent technology which also can be applied in the military equipments and other civil products. The Synchro moving gradienter equipment under the seat will adjust the users body barycenter to the level of the ground according to the different out-door terrain (such as curb, stair, pithead, uneven field). So you will feel balanced, and safe when drive on these boring terrain. It gives the real independence to the disabled people who thirst for going out to see the beautiful scenery. 1.258CBM