An ultrasonic surgical instrument , the instrument comprising: (a) a body , wherein the body defines a longitudinal axis, wherein the body is configured to receive an ultrasonic transducer ; (b) a shaft assembly, wherein the shaft assembly comprises an acoustic waveguide ; (c) an ultrasonic blade in acoustic communication with the acoustic waveguide; (d) an actuation assembly, wherein the actuation assembly comprises: (i) a first annular activation member , wherein the first activation member is disposed angularly about the body, (ii) a second annular activation member , wherein the second activation member is disposed angularly about the body, (iii) a first switch operable to enable one or both of the first or second activation member to trigger activation of the ultrasonic blade at a first power level, and (iv) a second switch operable to enable one or both of the first or second activation member to trigger activation of the ultrasonic blade at a second power level; and (e) a movable member , wherein the movable member is slidably movable relative to the body between a first position and a second position, wherein the movable member is operable to actuate the first switch in response to positioning of the movable member at the first position, wherein the movable member is operable to actuate the second switch in response to positioning of the movable member at the second position, wherein each of the first and second switches is configured to transition from an open state to a closed state in response to movement of the movable member between the first position and the second position. (a) a body , wherein the body defines a longitudinal axis, wherein the body is configured to receive an ultrasonic transducer ; (b) a shaft assembly, wherein the shaft assembly comprises an acoustic waveguide ; (c) an ultrasonic blade in acoustic communication with the acoustic waveguide; (d) an actuation assembly, wherein the actuation assembly comprises: (i) a first annular activation member , wherein the first activation member is disposed angularly about the body, (ii) a second annular activation member , wherein the second activation member is disposed angularly about the body, (iii) a first switch operable to enable one or both of the first or second activation member to trigger activation of the ultrasonic blade at a first power level, and (iv) a second switch operable to enable one or both of the first or second activation member to trigger activation of the ultrasonic blade at a second power level; and (i) a first annular activation member , wherein the first activation member is disposed angularly about the body, (ii) a second annular activation member , wherein the second activation member is disposed angularly about the body, (iii) a first switch operable to enable one or both of the first or second activation member to trigger activation of the ultrasonic blade at a first power level, and (iv) a second switch operable to enable one or both of the first or second activation member to trigger activation of the ultrasonic blade at a second power level; and (e) a movable member , wherein the movable member is slidably movable relative to the body between a first position and a second position, wherein the movable member is operable to actuate the first switch in response to positioning of the movable member at the first position, wherein the movable member is operable to actuate the second switch in response to positioning of the movable member at the second position, <EOS>