Our PRG shackles are unique in that they offer your choice of 1", 1.5", or 2" of lift. There have been handful of poor copies of our shackle that have come forth in the last year or so, but no one has been able to make a decent copy that offers all these units do at our price. Variable height options, chromoly sleeves, grade 8 hardware, laser cut and gloss black powdercoat (not spray paint or cheap cad plating). Installation is pretty simple and uses basic hand tools. You will need to drop the spare tire to remove the stock shackle on an Xterra though. We do NOT use grease on these or have zerk fittings...these operate like stock and do not require grease. We did design these with a slight bit of clearance at all pivot points to insure free movement and full articulation with out binding or harm to the springs or mounts. These can be combined with springs or AAL for more lift and/or articulation too. Note, on Frontier applications the 1" lift setting may requre grinding on the shackles cross-brace for clearance. Red shackles can take a week or more to ship.