This washer can be used to press the tip of the screws and bolts after inserting the panel, so as to achieve the effect of leakage. Jaws fit together with the threads for a strong effect. Main Material: SUS301-CSP; Main Treatment: Temper; Applicable Models: M6; Uses: Prevents screws and bolts from falling off; Caution: When tapping into the housing, please apply a smooth process. For installation, please use recommended jig and insert the screw parallel to the direction shown in the image. Otherwise, it may cause significant deformation in the washer. Even if it is parallel, some deformation may occur. To remove, press and rotate with a monkey wrench, or cut the washer with a nipper, etc. Once removed, product cannot be reused.