... opposite direction of the arrowhead. Notes:filters of big(small)roller should be changed every 40 hours 1 ... 2.Operation-select fat rolling function, cling the big roller to the slimming clothing. Vacuum mode: ... 3.Choose the fat slip function, use vacuum & small roller, fit for breast, arms, crus, thigh, cervix ... , from weak gradually to strong. 4.Vacuum&big roller suit for thick muscle, fleshy part, ...