This is the RDLogics Jato 2.5 and 3.3 Blue Aluminum Rear Axle Carrier Set.  These are much stronger than the stock plastic parts, and they look awesome.  If you want durability and a show quality part at the same time, these are what you need.

RDLogics parts are built with the racer in mind, and they are constructed of the highest quality materials. These are a must for high-performance vehicles and people who want the best.