It is disclosed an actuation mechanism for performing an action, where the actuation mechanism comprises: a first movable trigger assembly having a first trigger; a second movable trigger assembly have a second trigger, where the first trigger is movable independently with respect to the second trigger during a portion of movement of the first trigger and/or the second trigger; and a driving member in engagement with the first trigger assembly and the second trigger assembly, respectively, wherein, the first trigger assembly and the second trigger assembly are applied different mechanical advantages.