Two-way MAR-17-2-3:1 and MAR-23-2-3:1 speed reducers use traction drive technology-leveraged engineering fluids and precision manufacturing to achieve up 98% efficiency. MAR17-2-3:1 is designed for input speeds up to 3,600 rpm with 10 to 20 in/lb of torque. MAR-23-2-3:1 also is rated for speeds to 3,600 rpm but with an input of 20 to 30 in/lb of torque. The fluid has a coefficient of friction of just 0.1 to 0.12 transmits torque between the four driving and driven elements. The traction fluid changes continuously from liquid to solid to liquid in the microscopic spaces between the driving and driven elements. Despite no metal-to-metal contact, there is no slippage.