The focus of this paper is the weight reduction of a disc-type magnetorheological (MR) device. Two different designs are proposed and investigated via finite-element analysis (FEA) to achieve the optimum combination of design parameters that result in the highest torque-to-mass ratio. The FEA is performed using the non-commercial FEMM package. Due to the symmetrical structure of the device, a 2D-axisymmetric model is utilized to simulate the magnetic flux density distribution. The resistant torque calculations are based on the Bingham plastic model, assuming low shear rate of the MR fluid. The results are compared with a baseline design from literature. It is shown that, with simple improvements, the torque-to-mass ratio of the proposed O-Type MR device is three times higher than the baseline design while producing a similar resistant torque.