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SIG Sauer ROMEO4S Red Dot Sight - 2 MOA Ballistic Circle Dot Red Dot Sight SIG Sauer
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SIG Sauer ROMEO4S Red Dot Sight - 2 MOA Ballistic Circle Dot

£439.99
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Flexible returns

SIG Sauer ROMEO4S Red Dot Sight - 2 MOA Ballistic Circle Dot

Features

  • 2 MOA Dot with 65 MOA Ballistic Circle Reticle – Combines a precise central aiming point with a surrounding circle for quick target acquisition and holdovers.
  • Hybrid Solar and CR2032 Battery System – Automatically draws power from ambient light and seamlessly switches to battery in low-light conditions, offering up to 100,000+ hours of runtime.
  • MOTAC™ (Motion Activated Illumination) – Extends battery life by powering up on motion and shutting down when idle.
  • 12 Brightness Settings – Includes 10 daylight levels and 2 night-vision compatible settings for versatile use in all environments.
  • Precision Adjustments – 0.5 MOA click adjustments with ±50 MOA of total windage and elevation travel.
  • SpectraCoat™ Lens Coating – Anti-reflective coatings ensure maximum light transmission and clarity with minimal distortion.
  • Rugged Design – CNC-machined 7075-T6 aluminum housing with integrated steel shroud provides exceptional durability.
  • Waterproof and Fogproof – IPX‑7 rated for submersion up to 1 meter and nitrogen purged for fog resistance.
  • Quick-Detach Mount System – Includes both co-witness and low-profile mounting options.
  • Unlimited Eye Relief – Enables fast and flexible target acquisition across platforms.


Technical Specifications for SIG Sauer ROMEO4S Red Dot Sight - 2 MOA Ballistic Circle Dot

Specification

Details

Manufacturer

SIG Sauer

Model / MPN

ROMEO4S / SOR43021

SKU

SOR43021

UPC

798681567867

Magnification

Objective Lens Diameter

20 mm

Reticle

2 MOA Dot with 65 MOA Ballistic Circle

Brightness Settings

12 (10 daylight / 2 night-vision)

Battery Type

CR2032 with solar assist (side-loading)

Battery Life

Up to 100,000 hours

Adjustment per Click

0.5 MOA

Windage / Elevation Range

±50 MOA

Eye Relief

Unlimited

Housing Material

7075-T6 Aluminum with steel shroud

Waterproof Rating

IPX‑7 (submersible to 1 meter)

Fogproof

Yes – nitrogen purged

Weight

Approx. 7.6 oz (215 g)

Mount Type

Quick-detach co-witness and low mounts

Finish

Graphite / Matte Black

Country of Origin

USA

Warranty

Infinite Guarantee (housing); 5 years (electronics)

Included Accessories

  • SIG Sauer ROMEO4S 2 MOA Ballistic Circle Dot Sight
  • Quick-Detach Mount with Co-Witness and Low Spacer
  • CR2032 Battery (pre-installed)
  • Clear Flip-Up Lens Covers
  • User Manual
  • Warranty Card

SEO Keywords

SIG Sauer ROMEO4S, SOR43021, 2 MOA red dot, Ballistic Circle Dot, solar red dot optic, MOTAC reflex sight, QD mount optic, waterproof tactical red dot

Frequently asked questions

What is the return policy?

Our goal is for every customer to be totally satisfied with their purchase. If this isn’t the case, let us know and we’ll do our best to work with you to make it right. 14 day return if you are not happy. Things must be unopened and in original packaging, unless it is faulty.

Are any purchases final sale?

No, you can cancel at anytime and will receive a full refund. We will always work with you.

When will I get my order?

Shipping & Delivery

  • We work quickly to process and ship your order as soon as possible.
  • Once your order has shipped, you’ll receive an email with full tracking details.

Delivery Times

  • Standard delivery from our USA suppliers: 7–10 working days (usually within a week)
  • UK Stock Collection items ship within 24 hours.

Stock & Sourcing

  • Due to limited demand, we do not hold inventory in the UK. All products ship direct from our USA suppliers to us then we ship to you so you don’t pay any imports fees.

Insurance & Guarantees

  • Orders over £300: Free Royal Mail Special Delivery (Guaranteed Next Day, Fully Insured)
  • Orders under £300: Royal Mail Tracked service for £3.99
Where are your products manufactured?

Our products are manufactured both in USA and globally. We carefully select our manufacturing partners to ensure our products are high quality and a fair value.

How much does shipping cost?

Shipping & Insurance

Orders over £300 ship free via Royal Mail Special Delivery, guaranteed next day and fully insured.


Orders under £300 ship via Royal Mail Tracked for a flat fee of £3.99.

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Customer Reviews

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W
Wisit Khamsom
Fast shipping and amazing item

So authentic red dot, love it