USD189.99
 
This servo falls into between S8911BL and S8955SS.  It produces enough torque yet it keep speed at 0.08 at 8.4V.  It has very good potential to be your almighty servo.
 
[ Stall torque]43.2 (6.6V)/48.5 (7.4V)/55.0 (8.4V)kg・cm
　　　　　　　600.1 (6.6V) / 672.9 (7.4V) / 763.8 (8.4V)oz・in
[Speed] 0.10 (6.6V)/0.09 (7.4V)/0.08 (8.4V) Sec/60°
[Weight] 79 g / 2.79 in
[Dimension] 40 x 20 x 40.5 mm / 1.38 x 0.79 x 1.59 in
[Cable length] 300mm 
[Operational voltage] 4.5V – 8.5V 
■High performance brushless motor
■Programmable（slow start：ON）
■full metal gear
■full metal case
■wide voltage
■double ball bearings　Φ12 / Φ10
■angle：120°/180°（150° can be set by XBUS SERVO PROGRAMMER）
※ servo arm not included
 
The firmware in a 2k servo verifies the position of the servo arm two thousand times each second, 
while the firmware found in previous servos verify the arm's position one thousand times per second.
This greater number of verifications makes for a very precise servo, and gives it a more "solid" feel.
It is recommended to use a booster cable with 2k servos to ensure steady voltage at all times.