I've recently bought a couple of those cheapo 2t bottle jacks, just to tweak heights and stick the axle stands in the right place - interesting that it took well over 7t to fail and even that was progressive
BTW, the jacks with a U or Y top should have been packed to the proper load point before testing, as seen with the old screw jack which snapped it's locating 'ears' and then continued to take a huge load
