SparkFun will be closed Nov 26th and 27th for the Thanksgiving holiday. Orders placed after 2:00pm MT on the 25th will ship out Monday the 30th.

Creative Commons images are CC BY-NC-SA 3.0

$ 4.99

added to your
shopping cart

In stock 65 in stock
4.99 1+ units
4.74 25+ units
4.49 100+ units

Description: These couplers allow you to connect a 1/4” shaft directly to your C1 Hitec servo spline. The set screw included with each shaft coupler works well with straight or d-shafts. These servo shaft couplers have a length of 0.5”, an outer diameter of 0.42”, and an inner diameter of 0.25”.

Actobotics is a robotics building system based around extruded aluminum channels, gears, precision shafts, and ball bearings. Thanks to the two standardized hole patterns, nearly all Actobotics components can be intuitively connected together. The wide range of components makes building complex electromechanical prototypes or finished projects a reality.


  • Length - 0.5”
  • Outer Diameter - 0.42”
  • Inner Diameter - 0.25”
  • C1 Hitec Spline


Recommended Products

Customer Comments

  • Sparkfun should also carry the 525136 version of this which is compatible with the Futaba servos, ROB-11965 and ROB-9064 (25T spline).

Customer Reviews

4.5 out of 5

Based on 2 ratings:

5 star
4 star
3 star
2 star
1 star

Works as expected

Enough said!

Fits better than anything I could have done

24 tooth gear fits accordingly with a little bit of wiggle. It may be because the shaft I am using is approximately 5.5 inches long giving it some wiggle. But overall, this is better than any horn that you can get for or with the HS-311 servo.