It appears those Hell Bents are stock length and they want you to buy their drop brackets for lifted applications.
You want enough length on them to keep the sway bar at stock level, which is pretty much parallel to the ground. A sway bar becomes pretty much useless at over 20% of stock angle.
Now here's what I did on my Grand Cherokee when I lifted it 3". The only brand of extended lengths I could fine were $150 for the set, so I bought a set of new stockers off ebay for $22, cut and welded a solid piece of steel in the middle of them, 2 3/4" long which is what I measured I would need to keep the rear sway bar parallel to the ground.
Worked out quite well and saved me some serious coinage...
after they cooled off, I just hit 'em with some black rustoleum and on the Jeep they went...