The Daniel Defense RIS II is an innovative upgrade for the M4A1, M16A4, and MK18 CQB/R. The Daniel Defense Rail Interface System II (RIS II) was designed at the request of the United States Special Operations Command (SOCOM) for the SOPMOD II weapons system.  SOCOM had a specific requirement for a free float M203 40mm grenade launcher and Daniel Defense responded.  The RIS II allows the individual operator to free float the M203 grenade launcher without the use of additional parts or special tools.  This was accomplished by integrating all of the needed parts to free float the M203 into the rail itself.  After years of rigorous testing by Special Forces Operators, Daniel Defense was selected as the Sole Source Provider of the RIS II to SOCOM.  Daniel Defense has delivered thousands of units and they are currently being fielded by SOCOM units.  The RIS II is available in Black and Flat Dark Earth.

M4A1
Part Number:  DD-8001
NSN:  1005-01-547-2624
Weight:  16.5 Ounces
Length:  12.25”
Width:  2.36”
Armorer Installed
Free Float system designed to work in conjunction with a MK12 low profile gas block on an M4A1 or a standard M16A4

M4A1 FSP
Part Number:  DD-8030
NSN:  1005-01-566-5280
Weight: 16 Ounces
Length: 12.25”
Width: 2.36”
Armorer Installed
Free Float system designed to for use with an M4A1 with standard Front Sight Base

MK18
Part Number:  DD-8020
NSN:  1005-01-548-1385
Weight:  14.3 ounces
Length:  9.55”
Width:  2.36”
Free float system designed to use in conjunction with a 10.3” barrel and MK12 low profile gas block.
Armorer Installed
Not compatible with M203