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"Innovative firearm accessories engineered for performance"

SI designs rugged, user-focused firearm components and optics. They make accessories like slide plates, charging handles, barrel clamps, red dots, and shotgun parts.

5.0★★★★★(82 verified SI reviews)
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7,545
Products
2,384
In Stock
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Founded
USA
Origin

All SI Products (2,384)

Buy Sightmark SM34019 Tactical 30mm Cantilever Scope Mount Matte Black online Sightmark SM34019 Tactical 30mm Cantilever Scope Mount Matte Black Buy Sightmark SM13038CR1 Citadel 1-6x24mm Red Illuminated Rifle Scope Black online Sightmark SM13038CR1 Citadel 1-6x24mm Red Illuminated Rifle Scope Black Buy Sightmark LoPro Mini Green Laser Sight SM25016 - Compact Tactical Accessory online Sightmark LoPro Mini Green Laser Sight SM25016 - Compact Tactical Accessory Buy Sightmark LoPro Combo Green Laser & Light 300lm SM25013 online Sightmark LoPro Combo Green Laser & Light 300lm SM25013 Buy Sightmark SM26043-LQD Mini Shot M-Spec Red Dot 1x 3 MOA, 10 Brightness Levels online Sightmark SM26043-LQD Mini Shot M-Spec Red Dot 1x 3 MOA, 10 Brightness Levels Buy Sightmark SM39046 .380 ACP Pistol Boresight online Sightmark SM39046 .380 ACP Pistol Boresight Buy Sightmark Ultra Shot M-Spec FMS Reflex Sight online Sightmark Ultra Shot M-Spec FMS Reflex Sight Buy Sightmark Ultra Shot M-Spec LQD Reflex Sight online Sightmark Ultra Shot M-Spec LQD Reflex Sight Buy Sightmark Sm26032 Ultra Shot A-Spec 1X 33X24mm Obj online Sightmark Sm26032 Ultra Shot A-Spec 1X 33X24mm Obj Buy Sightmark Ultra Shot R-Spec Reflex Sight online Sightmark Ultra Shot R-Spec Reflex Sight Buy Sightmark SM26040 Element Red Dot 1x30mm 2 MOA Picatinny Mount online Sightmark SM26040 Element Red Dot 1x30mm 2 MOA Picatinny Mount Buy SightMark LoPro Compact Combo Green Laser Sight online SightMark LoPro Compact Combo Green Laser Sight Buy SightMark Ultra Shot R-Spec Reflex Sight - Dark Earth online SightMark Ultra Shot R-Spec Reflex Sight - Dark Earth Buy Sightmark SM26043DE Mini Shot M-Spec 3 MOA Red Dot Sight Dark Earth online Sightmark SM26043DE Mini Shot M-Spec 3 MOA Red Dot Sight Dark Earth Buy Sightmark Mini Shot M-Spec FMS Reflex Sight online Sightmark Mini Shot M-Spec FMS Reflex Sight Buy Sightmark SM13025001 Wraith HD Quick Detach Mount Matte Black Aluminum online Sightmark SM13025001 Wraith HD Quick Detach Mount Matte Black Aluminum Buy Sightmark SM13080HDR Core HX Black Hardcoat Anodized 3-12x56mm 30mm Tube... online Sightmark SM13080HDR Core HX Black Hardcoat Anodized 3-12x56mm 30mm Tube... Buy Sightmark SM11034T Latitude 20-60x80 Spotting Scope, Rubber Armor, Waterproof online Sightmark SM11034T Latitude 20-60x80 Spotting Scope, Rubber Armor, Waterproof Buy Sightmark Wolverine FSR Red Dot Sight 1x 28mm Matte Black Picatinny Mount online Sightmark Wolverine FSR Red Dot Sight 1x 28mm Matte Black Picatinny Mount Buy SIONYX C011500 Aurora Night Vision Monocular with Hard Case online SIONYX C011500 Aurora Night Vision Monocular with Hard Case Buy SIONYX C011600 Night Vision Monocular Black Premium online SIONYX C011600 Night Vision Monocular Black Premium Buy SIONYX K011400 Aurora Pro Explorer Night Vision Monocular online SIONYX K011400 Aurora Pro Explorer Night Vision Monocular Buy SIONYX Aurora Pro Color Nv Camera online SIONYX Aurora Pro Color Nv Camera Buy Silver Shadow Gilboa DBR Snake AR15 Rifle - Black 5.56 NATO 16" Double Barrel online Silver Shadow Gilboa DBR Snake AR15 Rifle - Black 5.56 NATO 16" Double Barrel Buy Sig Sauer P365 Fuse Semi-automatic Polymer Frame Pistol Compact 9MM 4.3" online Sig Sauer P365 Fuse Semi-automatic Polymer Frame Pistol Compact 9MM 4.3" Buy Sig Sauer P365 XMacro Striker Fired Semi-automatic Polymer Framed Pistol online Sig Sauer P365 XMacro Striker Fired Semi-automatic Polymer Framed Pistol Buy Sig Sauer 300 252 0409 11 9mm Optics Ready White Gold online Sig Sauer 300 252 0409 11 9mm Optics Ready White Gold Buy Sig Sauer 300 252 0409 64 9mm Optics Ready Blue Gold online Sig Sauer 300 252 0409 64 9mm Optics Ready Blue Gold Buy Sig Sauer P365X 300-252-0409-14 9MM 3.1" Gold Barrel 17 Rds Optic Ready online Sig Sauer P365X 300-252-0409-14 9MM 3.1" Gold Barrel 17 Rds Optic Ready Buy Sig Sauer 300-252-0409-04 P365X 9MM, 3.1" Gold Barrel, 17 Rounds, Black online Sig Sauer 300-252-0409-04 P365X 9MM, 3.1" Gold Barrel, 17 Rounds, Black Buy Sightmark Sm39043 Boresight Red Laser 300 Blackout online Sightmark Sm39043 Boresight Red Laser 300 Blackout Buy Sightmark SM39021 Boresight Laser .22LR Red 2 in Barrel Length online Sightmark SM39021 Boresight Laser .22LR Red 2 in Barrel Length Buy Sightmark SM39031 7mmx65 REM Premium Laser Boresight online Sightmark SM39031 7mmx65 REM Premium Laser Boresight Buy Sightmark SM39026 Triple Duty Universal Bore Sight .17 to .50 Caliber online Sightmark SM39026 Triple Duty Universal Bore Sight .17 to .50 Caliber Buy Sightmark SM39024 Boresight .17 to .50 Caliber Aluminum Magnetic In Case online Sightmark SM39024 Boresight .17 to .50 Caliber Aluminum Magnetic In Case Buy Sightmark SM26047 Mini Shot A-Spec M2 Red Dot Sight 1x23mm Matte Black online Sightmark SM26047 Mini Shot A-Spec M2 Red Dot Sight 1x23mm Matte Black Buy Sightmark SM39019 Boresight Red Laser .44 Mag Brass with Battery & Case online Sightmark SM39019 Boresight Red Laser .44 Mag Brass with Battery & Case Buy Sightmark Sm39018 Boresight Red Laser 38 Special/3 online Sightmark Sm39018 Boresight Red Laser 38 Special/3 Buy Sightmark SM39017 Laser Boresighter Cartridge 45 online Sightmark SM39017 Laser Boresighter Cartridge 45 Buy Sightmark SM39016 Red Laser Boresight .40 S&W Brass with Battery & Case online Sightmark SM39016 Red Laser Boresight .40 S&W Brass with Battery & Case Buy Sightmark SM39015 9mm Luger Boresight Red Laser 632-650nM Action Type online Sightmark SM39015 9mm Luger Boresight Red Laser 632-650nM Action Type Buy Sightmark SM13121MR2 Core TX 2.0 Rifle Scope 4-16x44mm MR2 Illuminated online Sightmark SM13121MR2 Core TX 2.0 Rifle Scope 4-16x44mm MR2 Illuminated Buy Sightmark SM39022 Red Laser Boresight 17 HMR Brass with Battery & Case online Sightmark SM39022 Red Laser Boresight 17 HMR Brass with Battery & Case Buy Sightmark Sm39020 Boresight Red Laser 22-250 Rem/6 online Sightmark Sm39020 Boresight Red Laser 22-250 Rem/6 Buy Sightmark SM39014 Universal Boresight .17 to .50 Caliber Brass Magnetic online Sightmark SM39014 Universal Boresight .17 to .50 Caliber Brass Magnetic Buy Sightmark SM39012 Laser Boresighter Cartridge 50 Caliber Chamber Brass online Sightmark SM39012 Laser Boresighter Cartridge 50 Caliber Chamber Brass Buy Sightmark SM39009 Red Laser Boresight .30-30 Win Brass with Batteries online Sightmark SM39009 Red Laser Boresight .30-30 Win Brass with Batteries Buy Sightmark SM17001 Wraith Mini Thermal Rifle Scope 2-16x 35mm Black online Sightmark SM17001 Wraith Mini Thermal Rifle Scope 2-16x 35mm Black

About SI

SI focuses on practical, performance-driven firearm accessories for a wide range of pistols, rifles, and shotguns. Their lineup includes slide adapter plates, latchless charging handles, barrel clamps, compact red dot optics, and dedicated shotgun components, built primarily from aluminum and hardened materials. Products are engineered with attention to fit, function, and ease of installation, aimed at shooters who want reliable upgrades without unnecessary complexity. SI supports competitive, tactical, and recreational shooters by offering parts that address common user needs and enhance firearm ergonomics and capability.

Headquarters

Established

-

Country of Origin

USA

History & Heritage

SI began as an American aftermarket parts maker aimed at providing functional, affordable upgrades and accessories for shooters. Over time the brand expanded its offerings across pistol, rifle, and shotgun platforms, becoming known for practical designs and broad compatibility.

Notable Products

Popular items include charging handles, slide adapter plates, red dot sights, barrel clamps, and shotgun conversion components.

Why Choose SI?

Choose SI for straightforward, well-engineered accessories that improve usability and durability without unnecessary complexity.

Ready to Shop SI?

Choose SI for straightforward, well-engineered accessories that improve usability and durability without unnecessary complexity....

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