Lancer Tactical Gen 4 M4 AEG Gearbox with GATE ASTER V2 SE ETU System, Black

The Lancer Tactical Gen 4 M4 Gearbox uses a built-in GATE ASTER V2 SE ETU and MOSFET. By replacing standard copper switch contacts with optical sensors, it delivers faster trigger actuation and precise gear cycle detection. The optical ASTER SE detects gear position through a complete cycle to prevent semi-auto lockups and double-feeding, while offering active braking, pre-cocking, adjustable trigger sensitivity, and low-battery protection. Settings can be programmed directly via trigger control or fine-tuned using GATE’s GCS app (via USB-Link or Blu-Link).

The die-cast V2 metal gearbox shell contains a full-metal gear set, a steel-toothed piston, a ported aluminum cylinder assembly, and a quick-change metal spring guide that lets you swap FPS springs without opening the gearbox shell. Power is routed to the rear through flexible low-resistance wiring terminated with a Deans plug for high-discharge 7.4V or 11.1V LiPo batteries. By eliminating physical trigger contacts, the optical sensor design removes electrical arcing and switch wear entirely. Finished in matte Black, this drop-in gearbox fits standard Version 2 M4/AR-15 lower receivers and retains standard V2 internal specs for future upgrades like 13:1 high-speed gears or high-torque long-type motors.

Features:

• Pre-installed GATE ASTER V2 SE Electronic Trigger Unit
• Optical sensors for fast trigger response and cycle detection
• Built-in MOSFET with battery and motor protection
• Fully programmable fire modes, binary trigger, and active braking
• Metal Gen 4 Version 2 gearbox shell
• Rear-wired low-resistance Deans power connector
• Drop-in compatible with standard M4 AEG receivers