An ultrasonic instrument for use during a surgical procedure includes a body, a shaft assembly, an ultrasonic blade, and an actuation assembly. The body is configured to receive an ultrasonic transducer for selectively generating a first or a second predetermined oscillation. The shaft assembly projects from the body and includes an acoustic waveguide connected to the ultrasonic blade. The actuation assembly includes an activator ring and an activation mechanism. The activator ring is selectively movable along the body such that the activator ring is accessible to be gripped by an operator around an entirety of an outer circumferential surface of the activator ring. The activation mechanism is connected to the activator ring such that the activation mechanism selectively moves along the body in conjunction with the activator ring. At least a portion of the activation mechanism is configured to selectively direct the ultrasonic transducer to oscillate the ultrasonic blade.
