Standard replacement / spare part for the R1B
Refer to your servo manual/specification to identify the correct spline tooth count required for your application.
R1 Wurks DD4 High Torque/Speed Low-Profile Servo has a 25T spline output.
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ARC A11 1/10th Electric Touring Car Kit
Elceram ELC021 G2 1/10th Oxide Brushless ESC with LCD Display
SRT BHMX2 i-BUS2 HV Ultra Low Profile Brushless Servo - 0.073s/18kg @7.4V
Fido 7000mAh 2S 7.4V 220C Super Low IR LCG Lipo Battery