Trijicon 100390 ACOG | 4×32 LED | .223/5.56 BDC | TA51

The Trijicon ACOG 100390 is a fixed-power 4×32 riflescope with an LED-illuminated green crosshair calibrated for .223/5.56 BDC. It pairs a compact, forged 7075-T6 aluminum housing with long-duration AA-battery illumination and a TA51 thumbscrew flattop mount for straightforward attachment to standard flat-top rails. The optic is designed for durable, consistent performance in a wide range of lighting conditions.

Product Specifications

• The UPC is 719307308183.
• The magnification is 4x.
• The objective diameter is 32mm.
• The reticle is an illuminated green LED crosshair calibrated for .223/5.56 BDC.
• The day reticle color is green.
• The illumination source is LED.
• The power source is a single AA lithium or alkaline battery.
• The specified battery life is over 12,000 hours on setting #4 using the supplied alkaline battery at 21°C (70°F).
• The mount included is a TA51 thumbscrew flattop mount.
• The housing material is forged 7075-T6 aircraft-aluminum.
• The finish is matte black.
• The adjustment rate is 2 clicks per inch at 100 yards.
• The eye relief is 1.5 inches.
• The exit pupil is 0.32 in (8.13 mm).
• The field of view is 36.8 ft at 100 yards (7°).

This ACOG model is built for users who need a compact, hard-use-capable optic with an easy-to-read illuminated BDC reticle for .223/5.56. Its AA-powered LED offers long run time and selectable brightness levels for use across a wide range of ambient lighting, while the forged-aluminum housing and proven sealing provide water-, fog- and shock-resistant performance. The included TA51 adapter allows mounting on flat-top systems without additional adapters.

Many users praise the ACOG for its rugged durability and consistent optical clarity, and others highlight the long battery life of the LED illumination as a major advantage.