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What’s Included | Specs | Pictures | Restrictions | Related Info

The ROMEO4XT-PRO is a compact rifle red dot that packs a lot of features into a small, lightweight package. The 4XT offers 50,000 hours of battery life from a standard AAA battery, several flip cover options, a killflash, and four swappable reticles. The included mount comes in at absolute height, but the included spacer can be installed to bring the optic up to a lower 1/3rd co-witness.


SIG SAUER ROMEO4XT-PRO; killflash; clear flip-up covers; solid flip-up cover (front); rubber bikini lens cover; multitool; T10 Torx bit; mount spacer; long mount screws; cleaning cloth

We include an 8.5″ x 11″ rifle zero target with every red dot. We recommend a 50/200 meter zero for most 5.56 rifles. (Click on the thumbnail for a printable version.)
How to Zero in 2 Minutes – Video – T.REX ARMS

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  • Users can select from 4 different integrated reticle options (Dot, Circle-Dot, Dot with Holds, Circle-Dot with Holds)
  • Uses an ultra-efficient red LED illumination for daylight visibility and extended runtime
  • 50,000 hour battery life
  • Runs on readily available AAA batteries
  • MOTAC (Motion Activated Illumination) powers up or down when sensing motion
  • Unlimited eye relief to acquire aiming point and target, regardless of eye position behind sight
  • Strong, lightweight aircraft-grade 7075-T6 aluminum housing
  • Waterproof, IPX-8 rated, and fog-proof

View all the reticle options HERE.

Assembled in the USA.

View the User Manual HERE.


Overall Length77 mm
Overall Width63 mm
Height56 mm
Weight7.4 oz
Center Dot Size2 MOA
Adjustment Increments0.5 MOA
Illumination Settings9 Daytime / 3 NV
Run Time50,000 hours
Battery Type(1) AAA
WaterproofingIPX 8

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This product cannot be shipped outside the US due to E.A.R. regulations.

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Our Most Recommended Rifle Upgrades – Help – T.REX ARMS

How Should You Set Up A Rifle? – Video –T.REX ARMS

LPVO Versus Red Dot + Magnifier – Video – YouTube

3 Tips to Shoot Rifle Better – Video – YouTube

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