THE 2-MINUTE RULE FOR COLT COMBAT UNIT RAIL GUN 45

I have RIA drawings specifing barrel markings on a fresh USGI rifle Which marking is not licensed.I assumed that aspect was attention-grabbing looking at I'd read which the colt handguards had been top quality.This handguard is not marked Never Take out, mildew marks are existing at each individual other circle (highlighted).  Take note placement