Mil-Stak, Inc. manufactures the Big-Bale Loader Stacking Arms (called loader clamps), an attachment for New Holland's self-propelled small-square-bale wagon that allows it to also pick up, stack, then unload mid-size (3'x3' and 3'x4') bales weighing up to 1,600 pounds. Operation is completely from the loader's cab and utilizes its existing controls. The switch to and from mid-size bale handling reportedly requires only a few bolts and hydraulic quick-couplers.