Designed to exceed the newest requirements of the US Army for improving zero retention/ repeatability.
- Upper three rail section mount underneath the end cap and secured in place with a friction fit ledge and roll pins.
- The receiver end secured with a barrel nut bracket that is atachedto the upper three rail section with four captive flathead screws.
- The bottom rail is secure with friction fit ledge and with a retractable spring loaded piston.
- Four full length rails - top rail creates one long monolithic rail with the existing flat top rail.
- XM4S has two push button sling swivel mounting points at the front.
- XM4SD has four push button sling mounting points at the front and back.
- Slots around the rails provide maximum ventilation around the rails.
- CNC machined from aviation grade aluminum to MIL-1913 standards with a hard anodized black oxide finish for durability and ease of maintenance.
- Accepts grenade-launcher.