The DS 97 is the upgrade of the DS92A+ with much better torque. It is possible by the a new stronger motor.
Servo Specification:
Torque (kg-cm) 3.8 (4.8V) / 4.3 (6.0V)
Torque (oz-in) 52.77 (4.8V) / 59.71 (6.0V)
Speed 0.070 s (4.8V) / 0.058 s (6.0V)
Stall Current (at locked load) 2.9A (4.8V) / 3.6A (6.0V)
Working Voltage 4.8V ~ 7.0V DC Volt
Working Frequency 1520μs / 333Hz
Dead Band 0.001 ms (Default)
Bearing 2* Ball Bearing
Gear Metal Alloy Gear
Motor Coreless Motor
Weight: 17.73 g (0.62 oz)
Dimension: 23 x 12 x 27.25 mm