Two rows of symmetrically arranges 25" serrated discs to mix residue into up to 5.5" of soil and cerate an ideal seedbed. The discs are set at unique angles to the soil and to direction of travel. The Rubin 10 does not need weight to penetrate the soil. Disc angle and speed pulls the machine into the soil. Ideal speed is 8-10 mph and HP requirement is approximately 15 per foot.