This is a set of two RPM HPI Blitz Rear Bearing Carriers, and are intended for use with the HPI Blitz, Blitz ESE, Firestorm 10T, E-Firestorm & E-Firestorm Flux. The stock rear bearings and axle carriers of the HPI Blitz, Blitz ESE, Firestorm 10T, E-Firestorm & E-Firestorm Flux aren’t quite strong enough to handle the punishment HPI owners dish out. Once again, RPM steps in to make a good product infinitely better! The primary focus was on a bearing overhaul. Stock bearings are a 5x10mm design, which is a rather unusual size and according to RPM customer reports, not strong enough for their demands. RPM Bearing Carriers use a 5x11mm bearing and if you’re familiar with the best selling RPM carriers of all time – the Traxxas Rustler, Stampede & Slash rear bearing carriers (#80382) – that use a 5x11mm bearing, you’ll already know how strong this bearing size really is. The typical bearing load rating difference switching from the stock 10mm bearing to an 11mm bearing nearly doubles (from 44kgf to 73kgf) the dynamic load rating! Naturally, while RPM was producing a new axle carrier, they went out of their way to make sure the overall design met standard RPM criteria for strength and durability. What they came up with is nothing but pure RPM muscle, sure to make even the most discerning customer extremely happy! RPM rear bearing carriers are made from RPM's bulletproof blend of super strong nylons and are factory backed with the industry renowned RPM breakage warranty. Coupled with the fact that they proudly produce every RPM molded product in-house in our facility in Chino, California USA means you’ll end up with superb, extremely high quality RPM products each and every time!