These are whal brothers extrovert drivers for 08-13 FX Nytro, 03-05 RX-1, 06-09 Apex, 05-09 Vector, 07-15 Phazer, 05-16 Venture. Sold as a set. Available in 7, 8 & 9 tooth. Starting in 2010 all vectors and apex models came with extroverts from factory.These will not fit 03-04 RX-1, 04-05 RX Warrior or 05 Rage unless the extrovert teeth are shortened to clear the front w-arm.