Omega 27036 Black Service Jack - 3-1/2 Ton Capacity Innovative Magic Lift design offers a quick lift for professional performance, US patent number: 5,755,101 Heavy gauge, steel frame helps prevent distortion and twisting; with one piece handle; handle with foam pad Built-in bypass device protects hydraulic system from over pumping damage US patent number: 5,946,914 Universal joint release mechanism provides precision control of load descent in any handle position Exclusively designed breather plug eliminates air in the hydraulic system, optimizing jack performance, US patent number: 6,318,403