Taper Roller Bearing. The intermediate shaft of the LT95 transfercase uses brass/bronze shims between the gears. There can be a lot of side thrust that beats up these shims, resulting in the gear cluster falling out of tolerance somewhat quickly. Heat, noise and abnormally fast wear result. Particularly when behind beefy engines. The TRB kit uses gears that have been machined to accept taper roller bearings for each gear in the cluster that effectively resist the side thrust. This mod was utilized by the AUS MOD for their 4BD1/4BD1T powered LT95 rovers in the mid-80s. Most of the TRB kits also utilize .996 high range gears, although some have 1.123.
1970 SIIA 88, Sold
1996 Disco I, RIP