They are standard al. bars but filled with some sort of solidified gel. The idea being the gel absorbs vibrations. Does it work? I can say yes. I noticed a big difference off the bat. The rides were not quite as harsh, allowing me to add more pressure to the front tire and not run so soft. I do not encounter soreness in my wrist like before or in my shoulders. (mind you they are wider then my other bars were so that might be a good factor in the shoulder aspect) If I rode primarily something like Walnut where it is not what I would call rocky and harsh then I wouldnt bother.
If you ride LGT, BC, CP or the GB where the chunk and shake factor is much higher then yes. The weight penalty is minimal and the ROI in places like that is good. They are not pricey , especially on sale