The new Garmin/Cervelo formation rides on Rotor cranks and when they test themselves against the clock, you can bet that they'll be riding with Rotor's 3D TT Crankarms. They're different from Rotor's standard 3D cranks in that they have a special aero-profiled spider. It's smooth on the outside, but intricately machined on the inside to relieve it of excess grams. Combine this with an aero chainring and you've got a slick little setup. Otherwise the 3D TT crankarms are structurally identical to the rest of their 3D offerings. They're light, stiff, and strong thanks to Rotor's Trinity Drilling System, a proprietary process that involves drilling out the center of the aluminum crankarms after they've been extruded into shape. Three parallel bores are made into the length of each arm -- the center bore from the spindle end, and two outer bores from the pedal end, towards the spindle. Through this process, Rotor eliminates excess weight while maintaining the stiffness you want and the strength you need. And the beauty! The CNC machine work and laser etched graphics give Rotor cranks a sinister, industrial appearance.Rotor's Spanish-made components meet all the stringent CEN safety standards. The system uses a 24mm hollow steel spindle that is pressed into the drive side crankarm. On the left side, the crankarm attaches to the splined end of the spindle and is secured with a DTT pinch bolt. Rotor's design with this dual threaded bolt eliminates much of the stress inherent in loading a standard pinch bolt system such as this. As an added bonus, Rotor's design includes a replaceable threaded insert in case you get a little hamfisted with the wrench, and the crankarm will be spared. The Rotor 3D TT Crankarms come with an anodized black finish and are available in three crankarm lengths -- 170, 172.5, and 175mm. Due to the aero design of the spider, they're available in 130mm BCD only. The crank is fully compatible with Rotor's Q-Rings and round chainrings as well as other manufacturer's five-bolt chainrings. The alloy spider attaches to the splined base of the drive-side crankarm and is secured with a lockring. It can be removed and swapped for another with a different BCD should you make wish to make the switch to compact gearing or install a crank based powermeter such as SRM or Quarq. Chainrings are NOT included and may be purchased separately. It can be used with the Rotor SABB or any other 24mm external bearing bottom bracket system built to Shimano's specs. The Rotor 3D TT Crank has a 147mm Q-Factor.