Optional R.A.S. panels are used on a rail where there is an accessory such as a Forward Pistol Grip mounted. The optional R.A.S. panels cover up the exposed part of the rail that is not covered by the accessory, they are available in 6 different lengths.
Panels are sold individually, not as a set.
NOTE: Flat Dark Earth is made to match Magpul FDE, Tan is lighter, Taupe is darker.