FMA CNC Low Profile 45° Rail for RIS Handguard — Tan

CNC-machined aluminium 45° offset rail by FMA, designed for shooters who have run out of mounting positions on RIS, KeyMod and M-LOK handguards on AR15 and M4 platforms. Installed at the 11, 1, 5 or 7 o'clock positions, it adds an angled section dedicated to accessories that would otherwise interfere with the standard 12, 3, 6 and 9 o'clock slots.

CNC machining keeps the Picatinny rail surface within consistent tolerances along its entire length — a necessary condition for optic mounts, torch mounts or PEQ boxes to hold their zeroed position without lateral shift. The low profile reduces bulk compared to full-height tower rails: the added accessory sits closer to the handguard body, leaving more room for a proper firing grip.

The mounting system uses 2 screws to anchor the base to the handguard and 4 screws to secure the Picatinny rail to the base. The two-piece design allows the rail angle to be adjusted before final tightening. One practical consideration: the two-stage screw arrangement provides greater rigidity than single-piece solutions, but both layers of fasteners should be checked after the first few shooting sessions, particularly with calibres that produce significant recoil.

Key points

• The 45° offset frees up the primary handguard positions and allows torches or lasers to be mounted in an operable window without rotating the weapon.
• CNC-machined aluminium keeps the Picatinny rail dimensions within the tolerances required for stable accessory retention.
• The low profile brings the accessory closer to the handguard, reducing the torque load on the mount and improving lateral clearance.
• Compatible with RIS, KeyMod and M-LOK handguards: a single component that fits the main handguard architectures on the market.
• The two-stage mount — base plus rail — allows orientation to be set before final tightening, using only the supplied screws.

In the box

• 45° mounting base
• Picatinny RIS rail
• 2 screws for attaching the base to the handguard
• 4 screws for attaching the rail to the base