Why do we name them DS-1?

The section of rear hub’s drive side is crucial…
While most rear hubs look similar - functionally, the drive side section of a rear hub bears significant importance. Modern rear hubs using speed cogs have a free hub body and a hub shell joined by an axle and a few bearings. A rider’s body weight and pedalling forces among others will stress this point between them (freehub and hub shell) leading to the axle flexing and putting the bearings under high stresses. It can be felt in instances like speed reductions during cornering and free-wheeling. An improvement on this area will have very little power loss and result in almost instantaneous power transfer during off-the-saddle moments, cornering, stationery moving off and any other high load applications. 
There’s no big secret how we designed a rear hub to excel at high-torque power transfers, ultra-low drag and to be the toughest out there. We just designed and invest in making and choosing the right parts! 
To prevent flexing at the section between the freehub and the hub shell, we increase the diameter of the axle at this area to 18mm (hub shell) and 20mm (free hub), couple with a 18307 bearing and a sleeve bearing on the freehub. In contrast, most rear hubs axles are designed between 15 to 17mm diameter throughout.

The sleeve bearing in the freehub is a clever solution to increase the strength and spread the load linearly rather than a single point if seal bearings are used. At the same time, it is very light and we use this savings on other parts of the hub. The sleeve bearings were sourced from Germany with high weather, heat and wear resistance coupled with extremely low-friction properties. As the sleeve bearing breaks in after some mileage, it conforms to axle’s surface at micron levels rendering the rear hub even smoother.