Shop for Pet Supplies & Wildlife at The Home Depot. The Step Over Gate Extension (Model SGX) works exclusively with the Step Over Gate (Model SG1). There s no limit to the number of extensions that may be added. Use one extension after another to create a very long gate span-great for blocking off large spaces or open rooms. One foot piece is included with each extension. The foot slides in order to control where it is positioned but can be permanently affixed if desired. Crafted of solid wood, the Step Over Gate Extension is available in White, Walnut, Oak, Natural.