A pipe wrench is provided with an extendable handle that fits within a cavity of the head. A lever locks the extended length of the extendable handle along a continuous spectrum between a maximum and a minimum extension of the handle. The lever includes cam surfaces. In an unlocked position, the thickness of the lever between the pivot and a friction plate is less than the thickness between the pivot and the friction plate in the locked position. The friction plate is a composite comprising a top lever plate, a midsection, and a concave surface. The lever plate and concave surface include hard, durable materials, and the midsection is a soft elastic material that redistributes frictional forces across the frictional block. The channel-lock prevents inadvertent overextension and/or accidental removal of the extendable handle.