Those are Sportcrafter Overdrive Pro rollers.

The rear drum with the red end cap has magnets inside which move as speed increases. This increases resistance progressively. It is pretty realistic and it is difficult to get them past 30 MPH with my road bike. Higher intensity intervals are totally doable with this drum. Engineers might enjoy the video below.


I also have a large free spinning "High inertia" drum for aerobic spinning and high cadence workouts. This is what I use for the fixed gear bike.

Great customer service. One of the drums was damaged when delivered. I was a knee-jerk, called the company and blamed quality control for allowing a faulty drum to be manufactured and shipped, blah blah, etc. The president of the company contacted me and based on the way it was broken explained that that the drum had taken a hit on the end cap during shipment, that there is no way they would have manufactured or shipped one that way. He shipped a new drum on the spot.

Lifetime warranty except for the belt. Made in Murica.


-Tim-