Green Beret's Newly modified Carbine M4 URGI

The Upper Receiver Group-Improved (URG-I) is a U.S. Army Special Operations Command (USASOC) program to further improve the durability and reliability of the SOPMOD Block II by introducing additional component improvements. First fielded in 2018, the main improvements are the lighter Geissele Mk 16 Super Modualr Rail that incorporates M-LOK as the mounting method and a Daniel Defense cold hammer-forged barrel that returns to the lighter “government“ profile contour as well as a mid-length gas system. Although initially an Army program, the URG-I has seen use by other components of SOCOM as well. Source: #Variants