Tamiya 1/10 Electric RC Car Special Edition No.156 1/10RC TB-05R Chassis Kit 47456. [Shaft-driven 4WD chassis ideal for the Tamiya Challenge Cup]. OP851 46mm Titanium Coated Suspension Shaft. The TB-05 allows you to choose between two motor mounting positions, front and rear, but the R is designed specifically for a front motor and uses a dedicated carbon-reinforced chassis and motor mount.