Continuously variable transmission, input number to get precise gear ratio, for balance it could be bigger than basic gearbox (2tall 1wide and deep for small, input top left, output bottom right, mimicking irl shape) with limited range, lets say 0-3, values lower than 1 will decrease ratio, higher than 1 increase, CVT could have limit to torque (or bad efficiency at high torque) with larger types having increased limit/efficiency (small for light truck/car, medium for larger haulers, large for trains, ships etc.)