I've had two Sears Aluminum jacks, Jeff has had one, and they have all failed miserably at their intended purpose. In fact, the second POS Sears aluminum jack is still in my garage. Come and take it away, free to any home. I think they work fine if you leave them in the box. Take one for a SCCA race weekend and she's a goner.

+whatever on the Harbour Freight ally jacks. I have one and it still kicking after six years. The Sears jacks failed within a few months.