... subcutaneous tissue, and then vacuum suction rollers roll forward and backward to do deeply and wave ... rollers; b. flat rollers Can do roll in, roll out, roll up, roll down, one roller fast one roller slow freely ... the motorized head for body treatment, roll in, roll out, roll up and one roller fast and one ... Frequency :0.1—5Hz Roller direction: roll in, roll out, roll up, one roller fast and one roller ...