Grizzly Trigger Unit PSJ-M2 Gen.4 Rear Wired

£69.99 inc VAT

Availability: In stock

The fourth generation of PSJ processor is our most advanced unit yet and one of the most advanced units in the world. The cut-off lever has been completely removed to ease the installation, energy consumption has been lowered even more down to 3.7mA and the fire modes have been updated to give you even more options. Also, some new functions have been added, including LED indication of proper installation of both the gear wheel magnet and the trigger magnet. All this is on top all the great functions previous generations had, like contactless magnetic switching, powerful MOSFET cooled via the whole gearbox, adjustable power of active brake with the possibility to disable it, programming by the trigger and so on.

GEN.4 updates overview

  • Unit size revised to fit into most gearboxes without any trouble.
  • Easier installation into your replica.
  • Cut-off lever not used at all.
  • Improved silicone wiring. Longer wires to allow use in any replica type.
  • Polarity of magnets does not affect functionality.
  • Updated fire modes now with the possibility to set mode independently for “semi” and “auto”.
  • Burst can now be set differently for “semi” (burst1) and “auto” (burst2).
  • Whole new mode SEMI.
  • Lower energy consumption, as low as 3.7mA.
  • Can be used with spring up to M210 with rate of fire 99rpm.


Function overview of processor unit M2 Gen.4

Fire modes

  • separate fire modes can be set for “semi” and “auto”
  • configurable burst mode – from 1 up to 255 BBs shot on one quick trigger pull
  • separate burst setting for “semi” (burst1) and “auto” (burst2)
  • automatically switches from semi to burst or from burst to full auto without any delay when the trigger is pulled for a longer time
  • modes are fully programmable by trigger itself


Rate of fire

  • allows you to set delay (in ms) between the two following shots
  • allows rate of fire setting (by % of the rate)
  • programmable by trigger


Special functions

  • default settings reset: You can simply reset all settings to their default values by the trigger
  • manual mode: If your PSJ indicates damage and you are sure it is not mechanical and your replica is able to shoot, you can access manual mode. In this mode, malfunction is ignored and you can fire on full auto mode only.
  • WARNING! By poor judgement, you can cause more damage to your replica and the unit!
  • SEMI only mode: Other fire modes will be ignored and the replica will shoot only on SEMI regardless of fire mode selected by selector (equals selector setting Safe – Semi – Semi)



  • no mechanical switch, switching is contactless
  • faster trigger response
  • increased rate of fire and battery life
  • maximum current up to 202A constant and 808A in peek


Active brake

  • stops motor immediately with the piston in the default position and spring loose (when 100% set)
  • increases lifetime of the piston, spring and many other parts
  • always finishes whole rotation of gear wheels
  • fully functional in all fire modes
  • adjustable by steps of 10%
  • possibility to completely disable active brake (set 0%)


Malfunction detection

  • the unit detects mechanical damage and disables shooting to prevent any other damage
  • user is warned by motor vibrations


Li-Pol/Li-Ion/Li-Fe battery check

  • when the lithium battery is discharged, unit warns the user by motor vibrations
  • battery type needs to be set – easily done using trigger itself
  • warning is off for Ni-MH, Ni-Cd batteries


Realistic trigger operation

  • trigger sensitivity can be set during installation to best fit your demands


Anti-reversal latch

  • solves the problem with a double shot on semi
  • anti-reversal latch may not be needed if the motor is powerful enough (not recommended)


LED indication

  • unit is equipped with LED indication for easier installation
  • LED located on the unit itself will indicate correct installation of the magnet on the piston gear wheel
  • indication supplements motor vibrations – it indicates what motor vibrations would
  • malfunction indication can be used to determine the correct installation of magnet onto the trigger


All this hidden inside your gearbox

  • the whole unit is installed inside your gearbox, replacing trigger contacts
  • only two power wires come from the gearbox


Generation 4 units are suitable for AEG replicas according to the version of gearbox each unit is designed for. Units have been tested in gearboxes of following manufacturers*: AimTop, APS, ARES, ASG Ultimate, Cyma, DBoys, Guarder, RetroArms, SHS, SRC

*Every manufacturer innovates their products over the time, so there is possibility, that the gearbox tested by us is different from yours. However this only means, that your installation might require some minor adjustments.

Technical parameters

  • powerful MOSFET with maximum current up to 202A constant and 808A in peak allows use almost without any restrictions
  • MOSFET is effectively cooled by the whole gearbox
  • the whole unit is coated in multiple layers of varnish for maximum durability even in poor conditions
  • replica‘s rate of fire is limited by gearbox components and technical specifications. PSJ unit itself is able to do up to 500 000 cycles (shots) per second. Unit is tested for 99 cycles (shots) per second
  • current consumption of unit in standby mode is as low as 3.7mA


Package contents:

  • processor unit PSJ gen.4 with complete silicone wiring and pre-installed insulation foil
  • modified selector plate with magnet installed (M2, M3)
  • heat-conducting foil
  • magnets
  • dean-T plug – male
  • gold-plated motor plugs – 2pcs
  • gold-plated fuse plugs – 2pcs
  • heat shrink tubing
  • fuse mini
  • user manual


WARNING: PSJ should be installed by qualified AEG professionals only! The manufacturer is not liable for any damage to the replica caused by unprofessional installation. Do not use soldering gun!


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