The ER-50eVo is our standard size retract system for models up to 30kg (66Lb) weight, backed by the guarantee of quality Electron is know for.

  • Compact design: The ER-50eVo main frame is milled from a single aluminium block, housing a spindle system with internal absorbers mounted between three bearings (two axial and one radial). All parts are very well protected inside the strong main body.
  • Light, strong and precise: The main body is milled from a single block of 7075 T6 aeronautical aluminium. Electron uses the latest industrial milling machines allowing the highest accuracy on all parts, resulting a system that is strong, smooth and without play.
  • Very easy maintenance: All rotating parts are made with self lubricating materials that require very low maintenance. Any damaged part can also be changed very easily. With just four screws you can completely disassemble the system and Electron Retracts can supply spares of all parts.
  • Reversible: All retracts purchased from January 2015 are a reversible version: this means that it can be operated in normal or reverse mode. This version also accepts trunions with all retraction angles (from 70º to 105º). Following this manual or see this video, the customer can disassemble the trunion in order to change the direction of operation or of the retraction angle (in this second case a new trunion with desired angle will be necessary)
  • NEW square spindle: this retract is now provided with a square thread spindle providing greater speed and torque to the system. Click here to find out more!

Weight (single retract): 290g
Trunion diameter holes: 7/16″,1/2″     8,10,11,12,13,14,15,16mm            
Trunion retraction angles: 75,80,85,90,95,100º
Steeerable  options: Servo plate, Electron steering system, Simple steering
Recomended battery: 500mAh Lipo 2s
Max current: 2.5A

Cycle Time:

  • High torque :  7seg.     8V   (NO LOAD)
  • Low torque:    3seg.     8V   (NO LOAD)


  • High torque:  110Kg./cm
  • Low torque:   50Kg./cm

Main dimensions:


Steeerable options:

servo plate

oie_transparent (2)

electron steering system

oie_transparent (3)

simple steering

oie_transparent (5)

inverted steering


  Servo Plate meassures: