This gas block replaces your existing front sight to provide a simple, low profile design that can be used to mount a rifle length forearm to a carbine length barrel. It is mounted by the use of two clamping screws. The two screws take a 9/64″ Allen Wrench

Specifications:

Manufactured from high quality steel and finished with a mil. spec. phosphate coating.
Length: 0.95″
Bore diameter of .750 inches.
Weight: 2.016oz

Made in the U.S.A.