GHK Colt Licensed M4A1 SOPMOD Block II MK18 GBBR Handguards and Rail Accessories Users should be alert that

Users should be alert that airsoft products are potentially dangerous which can cause serious injury and even death

A crush washer and shim kit are included to ensure proper alignment of the muzzle device onto your airsoft rifle

Gen 2 Design for better Air seal

Also works with Holosun HS403B red dot (does NOT work with 403R or 503R)

FEATURES of INVICTUS M-LOK Series Rails

GHK Colt Licensed M4A1 SOPMOD Block II MK18 GBBR Handguards and Rail Accessories Users should be alert thatComes with orange tip. Features Full metal upper and lower receiver with stamped Colt trademarks One piece metal barrel assembly CNC machined Daniel Defense licensed RIS II aluminum alloy handguard with laser etched trademarks allows for easy addition of any 20mm accessories Flat top receiver makes mounting optics or other accessories easy Adjustable CRANE style stock and polymer pistol grip CNC bolt carrier group with negative pressure blowback