Description Butler Round Jacks are utilized on a variety of trailer applications, from commercial to agricultural trailers and more. Butler A-Frame Jacks are recognized industry-wide as a quality product providing great value to the customer. Butlerâs A-frame Jacks are also available as jack stems, providing multiple mounting options. FEATURES: Ease of Cranking Smooth Operation and Handling Certified Vertical and Side Load Capacity Proven Reliability Options for Painted or Plated Inner and Outer Tubes