Available in Checkout
These are rollers to mount horizontally on both sides of a gate to help stabilize it from tipping over. They are sold individually but a pair would be required for true stabilization. They are made of rubberized UV protected hard plastic. Designed to stand up to the rigors of even the most extreme climates - these rollers will last for years and are maintenance free due to the internal sealed ball bearings. You can affix them to posts next to your gate via welding or bolting.
3" tall would be for gates with a flat top, 12" tall would be for gates that have an arch top (12" difference from trough to crest max) so the top frame will be on the roller at all times.