To use on a V2.1 GLA you need the following.
V2 Servo mount (GLA-V2-S015)
Aluminum servo horn for GLA (GL-0162-GLA)
OR
Plastic servo horn GLA Servo Saver set (DES131) (GLA-025)
 
 
 
 
1. It is with alloy case and titanium gears
2. It is ultra smooth compared with other servo of this size and provides a more precise feel in car handling 
3. It is for direct upgrade of GLA V1 stock servo （DES 131) and it is perfectly fit for GLA V1 or GLA V2 servo mount .(Not compatible with GLA V2.1 servo mount)
4. If user of GLA V2 wish to try its smooth feel, GLA V1 or GLA V2 servo mount is needed and to be purchased separately
5.Compatible with GLA servo saver set(GLA025)
Features:
Full alloy casing
Titanium gears
Bearing
Speed 0.05sec/60 @6.0V
Torque:2.30kg cm @6.0V