Use a T-10 tamperproof, Item # 49-0452-00

A set of instructions may be found in PDF format here:

Instruction Sheet

The logic to determine where the optic gun is pointed is on the host hardware, not the gun itself. There is no standard, but they all work basically the same way.
The theory for our guns, as well as most others, goes like this:

1. The gun does not emit light but senses the light from the monitor screen. The gun always sees a spot on the screen where it is pointed and gives a negative going 5 volt pulse to the game whenever that spot is illuminated. The signal is a pulse train of about 7 pulses, separated in time by whatever the horizontal frequency is, every time that particular spot is refreshed. (Only one pixel is illuminated at a time, but it's so fast it looks to the eye like they are all illuminated all the time).
2. The game knows which pixel on the screen is illuminated at any given time as it displays each video frame.
3. If the game gets a signal from the gun optics when it aims at an illuminated pixel and it knows which pixel is illuminated at any given time it therefore can determine where the gun is pointed on the screen.
4. If the trigger is pulled (negative going 5 volt pulse that stays low as long as the trigger is held) the game checks to see where the gun is pointed and determines if is a target or not and reacts accordingly.
5. A screen flash is done by the game (usually for one or two frames) whenever the trigger is pulled to make sure the gun can see a spot at that time. If this was not done, you would not be able to shoot dark targets because the gun would not see it.

Our gun is designed to work with CGA resolution, but will work up to VGA 640x480 @60 Hz resolution. It will not connect to a PC, TV or work with LCD or Plasma monitors.

RED +5 VOLTS
WHITE TRIGGER
BLUE OPTIC SIGNAL
BLACK GROUND

Pin 2 - GRN - Pump switch
Pin 3 - BLK - Pump sw Gnd
Pin 7 - RED - +5 volts
Pin 8 - WHT - Trigger switch
Pin 9 - BRN - Trig sw gnd
Pin 10 - BLU - Optic output
All other pins not connected. Connector is a 10 pin JST NH connector.