HG 1039-7 AR M4 CARBINE LENGTH FREE FLOAT QUAD RAIL by Xtreme Tactical Sports $45.00 1 2 3 4 5 6 7 8 9 10+ Quantity Quantity Add to cart AR/M4 Free Float/Quad Rail Carbine Length 6061 True Aircraft Aluminum Hard Coat Anodized Clamp on Custom Installation Required