Originally posted by S710_Nut
The S9550 is digital too go with the 3PK HRS?
S9550 is also flater/shorter by about 1mm from the metal gear (where you put your servo horn) to its mounting ears. Thats why with 2mm spacer in between the horn and plastic ball cup will not touch the belt when turning. I personally think this is the best fit servo for S710.