This gas block replaces your existing front sight and allows the use of dovetail mounted accessories. Installs easily with two cap screws onto barrels with a diameter of .625 diameter under the front sight. Purchase our dovetail mounted flip front sight (YHM-9584) to retain your iron sights. Gas port size: 0.125″

SPECIFICATIONS
Made from high quality steel and finished with a Mil. Spec. phosphate coating.
I.D.: 0.625″
Length: 1.85″
Weight:5.12 Oz.
Made in the U.S.A.