Its the same drum I used in the previous robot:

A titanium drum, with 8 pussycat style teeth, powered by a LEM-130 at 36v, it spins upwards to flip as well as rip. There is also a 3.25mm hardox scoop underneath the drum to give it 0 ground clearance, it is 25cm in diameter and spans for the full width of the robot, it weighs 8kg