HEAVY DUTY DOCK BUMPER TOUGH PLIES OF FABRIC IMPREGNATED RUBBER PADS ARE COMPRESSED AND SECURED BY 3/4"" THICK STEEL RODS AND MOUNTED TO 1/4"" THICK ANGLE IRON BRACKETS. ABSORBS OVER 80 OF THE IMPACT FORCE. PRE-DRILLED 13/16"" ANCHOR BOLT HOLES OFFER QUICK INSTALLATION. ALLOW 12"" BETWEEN EACH BUMPER FOR DEPENDABLE PROTECTION. WARNING: This product can expose you to chemicals including lead which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65warnings.ca.gov - 1,3-Butadiene