The Geissele Automatics Super Gas Block is designed to fit barrel that are .750" in diameter. These gas blocks are made by Geissele and they are the perfect addition to any upper or rifle that you want to add a Geissele free float tube to.
Specifications and Features:
Geissele Automatics AR-15 Super Lo-Profile Gas Block 05-231C
Lo-Profile Gas Block
.750" Barrel diameter