This is a Diamondhead USA, Inc. Rail known as the VRS-T Free-Floating Handguard, model 2215.
Diamondhead's VRS-T-556 10.25" Free-Floating KeyMod Handguard Rail offers an uninterrupted rail extension and handguard in perfect alignment with the host weapon's flat top receiver. The "T" rail replaces the factory delta ring and barrel nut. The VRS T-KeyMod-556 Free Floating Handguard System provides excellent flexibility of use when adding KeyMod configured accessories. Pair the VRS T-556 with the Diamondhead T-Brake (5.56mm) for optimal muzzle compensation & appearance.
Features:
Sturdy lightweight free float design;Flush mounted Picatinny top rail;Configured for KeyMod accessories on sides and bottom;10.25 in length