The Special Operations Peculiar MODification (SOPMOD) kit is an accessory system for the M4A1 carbine, CQBR, FN SCAR Mk 16/17, HK416 and other weapons used by United States Special Operations Command (USSOCOM) special forces units, though it is not specific to SOCOM.

The kit allows US Special Operations Forces personnel to configure their weapons to individual preferences and customize for different mission requirements.

The Daniel Defense M4A1 features the M4A1 RIS II, which has been in use by US Special Operations Command (SOCOM) for the SOPMOD Block II program since 2005. The M4A1 features a 14.5” Cold Hammer Forged M4 Profile barrel with a Daniel Defense Flash Suppressor.