On reach trucks, the 3rd post is to protect the operator from coming in contact with racking or other obstructions. Order pickers don't have them because they are designed to be used with a pallet on the forks, which keeps operator away from racking. They also generally travel alongside racking while reach trucks turn around in aisles
This is ONLY to be used to report flooding, spam, advertising and problematic (harassing, abusive or crude) posts.