M4 Tracer Unit Instillation
M4 Tracer Unit Installation.
Thanks for purchasing your hop up tracer unit.
This component should be fitted by a professional Airsoft Technician. Also see the Flat
and R-hop installation guide for tips.
The fitting procedure is fairly straightforward, please note polarity is important.
Incorrectly wiring this unit could cause damage.
The unit is not supplied with a fuse as the type and placement will be different in
every gun. If you feel there is any possibility of a short circuit, fit a fuse.
Please follow the step by step guide. The kit has been designed to be made up from
separate units for ease.
The kit comes with all the parts needed for most builds, unless you require a longer
lead to run from the switch to the hop unit or you are fitting without the switch no
soldering is required.
1.The parts you need
2. Setting up for your battery
Select the correct balance plug, shorter for 2 cell (typically 7.4V LiPo) longer for 3 cell
(typically 11.1V LiPo or 9.9V LiFe) and attach the 2 pins from the power regulator into
the 2 holes either side of the plug. Be sure to fit the correct polarity (black to black
red to red)
Next apply the shrink wrap as shown and some glue gun glue to make sure the pins
can’t push out. This doesn’t need to be too neat but make sure it’s stuck well.
Place the larger piece of shrink wrap over the connector, if necessary you can stretch
the shrink-wrap to make fitting easier.
When this is heated the glue will melt inside and make the whole thing well protected
3. Switch position
The advantage of an external switch is its easy access. Switching off the light source
in situations where even the low visible light given off by the UV LED’s could give your
position away. Battery power can also be conserved.
It’s worth spending a little time deciding where you want the switch and which way
around it will be best to go.
Often the best and simplest method is to mount it on a rail section on the barrel hand
guard and run the power supply wires through the wire hole under the barrel and the
supply to the hop back the same way. Another method could be to open the hole up
where the gas tube fits in the body
Also considerer the route for the power supply wires. These wires have been left long,
don’t be tempted to cut them too short until you have at least test assembled it all
4. Wiring everything up
Please be aware!!
Black is not always negative! The wires that may come with your unit and go from the
switch to the hop could be coloured black and white. In this instance….
Black = positive +
White = negative –
This doesn’t make sense to me but it is what it is, so do not confuse this when wiring
into the switch!
Also avoid disconnecting this small plug by pulling on the wires.
You have 4 wires to get in this terminal block (this can be frustrating but please avoid
swearing so much you open a portal to hell!). Now is a good time to think about using
some of the shrink wrap on the wires but don’t shrink it in place yet!
The easiest way seems to be to push one wire at a time through one of the 3 wire
slots in the switch. Bring enough through so that you can create a loop and push the
end down into the terminal block. The port in the block can be opened up with the
screwdriver pushing against the screw head in the back side of the switch. The 2 red
ports will take the positive supply from the battery and the positive wire to the hop
(so could be black!). The 2 black ports take the negative supply from the battery and
the negative supply to the hop (which could be white!).
Once all your wires are connected up and secure its worth giving the unit a test. Plug
the small connector in to the hop unit and connect a battery. With the switch in the
correct position the LED’s should glow inside the hop unit.
6. Assemble the hop unit
This goes together like any other hop unit but have a look at our flat/R-hop arm
installation guide for a few tips.
7. Final assembly
Once you’re happy everything is functioning as it should be, fit the switch unit to your
desired position. The silver grub screw can be wound in and put in a slot in your rail to
stop it moving, do not over tighten! this is just to apply enough pressure to stop it
moving and over tightening could damage the switch unit. Hopefully you put some
shrink wrap on the wires coming out of the switch unit (step 4). This isn’t necessary
but will protect and neaten the wires, we don’t recommend shrinking this in place but
instead work the end of it into the wire axes hole to make it look neat.
Finally connect the plug into the hop unit and close your gun. Then your done, go get
to a low lit game.
Any queries don’t hesitate to contact us through Facebook or directly emailing