Strong, durable, and sturdy, the BULLDOG 12,000 lbs. support capacity square jack is the BIG reason why BULLDOG has carried the load in agricultural, construction, heavy-duty utility, and horse/livestock trailer industries since 1923. All BULLDOG 4" square jacks are rated for 12,000 lbs. support capacity and 10,000 lbs. lift capacity. The strength of the product, plus the wi...