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to provide a fast, secure, and enjoyable experience. by drg, from OR, United States Asked on August 7, 2022
The Aero Precision M4E1 16in .300 Blackout Barrel Complete Upper Receiver uses a low profile 0.750" gas block. An adjustable gas block could be used, however, a larger inside diameter handguard may be required depending on the gas block you intend to use. The internal diameter of the included handguard is 1.78".