The internal dimensions of the Method Dynamics Elite Handguards are designed to allow the maximum clearance for gas blocks and gas tubes. The three bolt clamp barrel nut attachment system with indexing set screws creates a muchmore rigid handguard than traditional two bolt designs. Front and rear flush cup sling swivel attachment positions with timed detents allowing the user to index the position of the swivel instead of allowing it to spin. FeaturesInterrupted M-Lok Top with front and rear picatinny rails.M-Lok Slots on top, sides, and bottom.Steel Barrel nut-requires only a simple wrench to tighten.Steel anti-rotation device to keep the receiver and handguard aligned perfectly.