13.2-Ton Professional Grade Jack Stands provide a stable and safe support for all heavy trucks. Entirely made of steel, their wide pyramid base is industrially welded to meet rigorous safety standards for automotive service equipment. Their build quality is unquestionable; they are robust and made for long-term durability. Adjust their height by slotting the pin into one of the holes along the center tube.SAFETY WARNING: Never get under a vehicle that is not supported by a certified and proper jack stands. Validate lifting capacity before use. Correct and proper use of floor jacks and jacks stands can prevent injury and/or death.