Boerboel 73014317 Self Closing Device Designed for farm gate applications. Kit includes 1 self-closing device, 4 - 1 1/2" hex head self-drilling lag screws, and 1 allen wrench. Easy installation on posts 4" or larger and gates with 1 3/8" to 2 1/2" or larger upright dimensions. Made out of Zinc Plated Powder Coated Steel, ASTM B117 Salt-Spray tested and passed. Unmatched protection for unmatched gate hardware, with the warranty coverage to prove it. Covered by our Limited Lifetime Warranty, you can rest assured that your investment is well protected.