Shimano's genuine 10 speed mountain bike derailleur jockey wheels come in 3 different quality levels.
The top of the line "Premium Grade" XTR wheels feature fully sealed cartridge bearings, lighter weight and a mud shedding design. These come stock on XTR 980/985 and Saint 820 derailleurs.
The mid tier "High Grade" XT jockey wheels keep the sealed bearings, but loose the lightened/mud shedding design. Standare equipment on 780/785 derailleurs.
The "Standard Grade" SLX jockey wheels round out the range and are standard equipment on SLX 670/675, Deore 610/615 and Zee 640 series derailleurs
Each jockey wheel kit includes:
1 x 11 tooth Pulley wheel
1 x 11 tooth Tension wheel