The Wera 6004 Joker S 10mm - 13mm is a self-setting adjustable spanner wrench designed for a wide range of applications. It automatically adjusts to different metric and imperial screw sizes, featuring continuous and parallel jaws that replace multiple single spanner dimensions. The integrated lever mechanism securely clamps the hexagon bolt or screw, significantly reducing the risk of slipping or damage. Its ratchet function ensures fast and consistent action without needing to remove the tool. The design allows for a small back-pivoting angle of only 30 degrees, making it highly efficient for high-speed working.