Post Guide-On 65" - GalvanizedThese post guide-ons serve the same purpose that all other Smith post guide-ons do, however these include metal uprights made of a thicker 12 gauge steel that has been hot-dip galvanized for greater corrosion resistance, making this set of post guide-ons ideal for heavy salt water use. This guide-on fits channel frames up to 4” wide by 5-1/4” tall, and any size of I-beam frame due to the two mounting options included. The metal uprights can be adjusted up to 19” out from the side of the frame.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.