flanger fa-11 pro piano exerciser owner's manual piano electronic keyboard hand finger exerciser tension training trainer

exercise each finger individually. improves user control of bats, racquets, clubs, guitars, and piano. provides wide range of tension for strengthening fingers , hands , wrists , and forearms perfect tool for pre-show warm-ups and maintaining conditioning when away from your instrument. conditions and builds strength in fingers, hand, wrist, and forearm, in compact package you can take anywhere