Bulldog Trailer Jacks are the unquestionable leader in the trailer industry. Since 1919, Bulldog has been manufacturing the industry's most trusted products for heavy duty applications. Whether it's for livestock trailers, utility rigs, or cargo haulers, every rugged and proven Bulldog product is certified ASABE S485 compliant - the "gold standard" in proven performance for telescopic screw-type jacks. Bulldog Trailer Jacks offer you proven quality, performance, and versatility. Our wide range of products has you covered whatever your application. When choosing a trailer jack, it's crucial to be sure you've picked the right equipment for your needs. Our Bulldog Round Jacks offer you proven performance for supporting lighter loads during coupling and uncoupling and for stationary support. Bulldog Square Jacks and Heavy Duty Square Jacks provide the right combination of medium-and heavy-duty support during coupling and uncoupling, and when storing your trailer. For heavy-duty loads where a combination of speedy operation and a variable cranking ratio is needed, Bulldog 2-Speed Square Jacks are a good solution. Rack and Gear Jacks are stability and support for higher tongue weight trailers. They also offer a convenient way to position your rig on the drive or the work site. Bulldog also offers a wide range of accessories and replacement parts to keep your rig operating at peak performance. Be sure to check out the Bulldog jack that fits your application, weight rating, and features. No matter what equipment you choose, you can rest assured that Bulldog legendarily rugged performance pedigree is built into every product we manufacture.