You can easily level the heaviest cabinets. Each set (4 pc) has load bearing capacity of 600 lbs. The bottom lip carries the weight of the cabinet.
Minimum installation height is 3".
The manufacturer states the weight capacity of these legs are 600 lbs (which is a lot of weight). Even though this is the manufacturer's endorsement, we recommend the load bearing capacity of 400 lbs per 4 piece set.
BlackJack levelers I used them on a workbench that has 2x4 legs. I can move my table around and if it's not stable I simply lower a foot. The metal lip that goes under the table leg is big enough to support it and keeps the wood off the floor which is nice if your floor gets wet.
I can add up to 1 1/2' of height to my table. This allows me to raise it to the height of my saw to use as an in/outfeed.