A wrench is a form of LEGO Tool. Wrenches serve both practical and aesthetic purposes. Although they cannot physically tighten blocks, some models can lock onto studos.
It has 3 different variations. One variation is more similar to a pipe wrench and is very large. The second variation can click on to bricks and has another end like that of a crowbar. The third wrench is the smallest and comes on tool racks that are common and in many LEGO sets.