Zinc Coupler Safety PinSpring locking action secures the coupler clip and prevents accidental uncoupling.. Zinc plated steel. 1/4" pin shank fits all couplers. 1-3/4" usable length. 1-1/2" clearance under spring arm. Coupler not included.WARNING: This product can expose you to chemicals including LEAD,Chromium (hexavalent compounds) which are known to the State of California to cause cancer, birth defects or other reproductive harm, and NICKEL (METALLIC),COBALT METAL POWDER,BERYLLIUM which are known to the State of California to cause cancer, and ARSENIC ,CADMIUM which are known to the State of California to cause cancer or other reproductive harm. For more information go to P65Warnings.ca.gov.