It's just a cone filter placed on the end of the line. Took out the stock intake filter box, a filter with a 3.25" opening fits perfectly on the line. Sounds nice but any improvements are debatable. Personally I'd probably go with a decent exhaust before CAI, but it's probably best to combine the two for the least amount of resistance. Combined with a DPF delete you'd definitely see some improvements. Next time I get a chance I'd like to stop in a muffler shop and have a straight pipe made up in place of the DPF, the only issue with that is what type of flanges they use since they may be hard to come by.
2008 GC CRD, OME 2" lift kit, 265/70/R17 Cooper Discoverer S/T's, 1.5" Spidertrax spacers, gutted turbo resonator