B&T Mounting Rail NAR Lateral

B&T Mounting Rail NAR Lateral — For TL99 Handguard (BT-401003) — B&T-21193

Expand or restore the side-mounting capability of your B&T TL99 handguard with the B&T NAR Lateral Mounting Rail (B&T-21193). This is the factory OEM lateral rail designed exclusively for use with the B&T TL99 Handguard (BT-401003) for the HK MP5 — it is not a universal rail and will not fit other handguard systems. Whether you're replacing a damaged or missing side rail, adding an additional lateral mounting position, or simply sourcing a factory-spec replacement, this is the correct, purpose-built part straight from B&T.

The TL99 handguard for the MP5 features NAR/Picatinny rails on each side and on the bottom, and the BT-21193 is the lateral rail component that populates one of those side positions — ensuring your TL99 retains its full modular accessory capability for lights, lasers, foregrips, and other MIL-STD-1913-compatible accessories.

Key Features:

• TL99 Handguard Exclusive Fit — Engineered specifically for the B&T TL99 Handguard (BT-401003) for the HK MP5 — not compatible with any other handguard or rail system
• Factory OEM Replacement — Genuine B&T replacement lateral rail, ensuring correct fit, finish, and rail height consistency with the rest of the TL99 handguard system
• NAR / MIL-STD-1913 Picatinny Compatible — Accepts the full range of standard Picatinny-compatible accessories including tactical lights, lasers, and foregrips
• Lateral (Side) Mounting Position — Installs on the side of the TL99 handguard to provide a dedicated lateral accessory mounting surface
• Swiss-Engineered Quality — Manufactured by B&T (Brügger & Thomet) to exacting tolerances, ensuring consistent rail height and alignment with other TL99 rail sections
• Durable Construction — Built to the same standard as the host TL99 handguard, designed to withstand field use and sustained recoil without loosening or shifting
• Precise Rail Alignment — Properly calibrated rail height ensures accessories mount flush and function correctly alongside other TL99-mounted accessories

Important Compatibility Notice: This lateral rail is exclusively compatible with the B&T TL99 Handguard (BT-401003) for the HK MP5. It will not fit the standard B&T MP5 3x NAR handguard (BT-21358), any other B&T handguard, or third-party rail systems.

Specifications:

• Manufacturer: B&T (Brügger & Thomet)
• Part Number: B&T-21193
• Compatible Handguard: B&T TL99 Handguard — BT-401003 (HK MP5) only
• Mount Type: Lateral NAR / MIL-STD-1913 Picatinny Rail
• Position: Side (Lateral)

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