Originally Posted by
scottryan
There is a standard piece of equipment used for all of these. A quick rundown of the main stuff follows:
The Knights Armament RAS is the standard handguard used on the M4 and M16A2/A3/A4.
The standard BUIS is the Matech.
The standard foregrip is the Knights Armament vertical grip.
The standard optics are the Aimpoint M2 (M68), TA31F ACOG, and TA31RCO ACOG.
In special operations command, there are some different pieces of gear that are standard on the M4A1.
The Knights Armament RIS is used.
The standard optics are the TA01NSN ACOG, the TA01ECOS ACOG.
The Knights 300m BUIS is the standard rear sight instead of the Matech.
You will find other pieces of gear being used. These would come from commercial sources and are not a standardized item.