A wrench comprising an elongated handle having a proximal end and first and second pivots at a distal end, and a spring-loaded latch pivotally connected to the second pivot, the latch being movable about the second pivot from an unlocked position to a locked position. The wrench includes a first clamping jaw having a first end pivotally connected to the handle at the first pivot and having a second end that includes a third pivot. A second clamping jaw is pivotally connected to the first clamping jaw via the third pivot to constitute with the first clamping jaw an articulated clamping jaw. The second clamping jaw has a free end for displacing the spring-loaded latch from the unlocked position to the locked position. The latch locks the free end of the second clamping jaw when the free end of the second clamping jaw has pushed past the latch.