Or as low as 
With a growing demand, ROTOR is committing to a separate mountain bike crank line named “REX”.
The additional line, with its own designation and design will help to clearly distinguish the ROTOR MTB from the road crank line. The new REX MTB cranks are based on the same successful “Trinity Drilling System” technology as all ROTOR cranks, which helps reduce weight and maximize stiffness.
The REX line will come in different levels which will have a new nomenclature.
For example, with the REX 1.1 crank, the first number indicates the level, 1 being the highest, and the second number indicates the number of rings, in this case it is 1 single chainring, the new QX1 ring. REX1 BCD 76 •The lightest crank in the mountain bike line is built around a new 7055 alloy. •Available in single ring (REX 1.1) •BB30 •175mm crank arms
