A hinged handheld tool that includes an integrated power transmission mechanism to allow a user to increase an output pressure onto an external object. The handheld tool includes a first tool-part assembly and a second tool-part assembly, wherein each includes a hand lever, a jaw-receiving cavity, an independent jaw, and a cam. The independent jaw engages the external object and comprises an engagement end and a tapered end. The hand lever is the grasping element for the user. The hand lever of the first tool-part assembly and the second tool-part assembly are terminally and pivotably connected to each other about a fulcrum axis. The independent jaw is pivotably connected to the hand lever within the jaw-receiving cavity. The cam is rotatably mounted within the jaw-receiving cavity, in between the hand lever and the tapered end. The cam and the tapered end are mechanically coupled to yield a ratchet-type mechanism.