Abstract: A ratchet wrench includes: a main body having a first accommodating space; a tool head disposed removably within the first accommodating space and having an annular groove formed in an annular peripheral surface thereof, and a ratchet tooth portion; a direction control unit including a pawl block, the pawl block having a middle portion connected pivotally to the main body, and two pawl tooth portions flanking the middle portion; and a covering unit including a mounting plate, and an insert member disposed movably on the mounting plate and biased to engage the annular groove.

Abstract: A ratchet wrench includes: a main body having a first accommodating space; a tool head disposed removably within the first accommodating space and having an annular groove formed in an annular peripheral surface thereof, and a ratchet tooth portion; a direction control unit including a pawl block, the pawl block having a middle portion connected pivotally to the main body, and two pawl tooth portions flanking the middle portion; and a covering unit including a mounting plate, and an insert member disposed movably on the mounting plate and biased to engage the annular groove.

Abstract: A Fall-risk Evaluation and Balance Stability Enhancement System and method evaluate and treat the sense of body balance. It is focused on measuring the center of pressure (COP) information, evaluating fall risk by the noninvasive physiological signals machines, and improving the body's balance and stability by stimulating physical treatment in feet.