A couple of years ago I bought some 12-ton jack stands from HF. The first time I used them they both collapsed as soon as I lowered the front axle of the Jeep onto them. I discovered that the pawls were cast steel, and VERY roughly cast. They just didn't have teeth to sufficiently engage the matching teeth on the riser. I took them back. About a year later I was hanging out at Avery's place when a HB 12-ton jack stand collapsed under Bricker's jeep, with Bricker sitting on the ground right next to it. Thankfully, no one was under it. BE WARNED -- I'VE PERSONALLY SEEN HARBOR FREIGHT 12-TON JACK STANDS FAIL TWICE. ITS A PIECE OF CRAP PRODUCT AND NOT WORTH THE RISK, in my opinion.
BTW, lest anyone think I just have some sort of axe to grind with HB, I have owed a set of their 6-ton stands for years and use them regularly.