The barrel ships with a Noveske gas block installed. This barrel is designed for Noveske's gas block, which is 1" long (INCLUDED). A standard front sight base is 1.9" long and WILL NOT FIT. Barrel installation should be performed by a qualified gunsmith. Installation of the gas block dowel pin and gas block is required to complete the assembly process.
All NFA Regulations apply. Please check your local and state laws before ordering. Contact your local ATF Field Office with any NFA questions you may have.