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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
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2,384
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Founded
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All SI Products (2,384)

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Buy Sig P320 10MM X-SERIES 5 OPTIC READY 15RD COY online Sig P320 10MM X-SERIES 5 OPTIC READY 15RD COY Buy Sig Sauer 1911X RX 45AP 8+1 X-Ray3 Sights Romeo-X Red Dot Black DLC online Sig Sauer 1911X RX 45AP 8+1 X-Ray3 Sights Romeo-X Red Dot Black DLC Buy Sig SAUER P365 2A 9mm 3.1" XRay3 Sights 2x10rd/1x12rd Pistol 365-9-CXR3P-2A online Sig SAUER P365 2A 9mm 3.1" XRay3 Sights 2x10rd/1x12rd Pistol 365-9-CXR3P-2A Buy Sig Sauer SOZ10002 Zulu10 HDX 10x50mm Binoculars, Coyote, Waterproof online Sig Sauer SOZ10002 Zulu10 HDX 10x50mm Binoculars, Coyote, Waterproof Buy SIG SAUER P320-XFIVE SXG 9mm 5in 3 21rd Mag Semi-Auto Pistol 320SXG5-9-STAS online SIG SAUER P320-XFIVE SXG 9mm 5in 3 21rd Mag Semi-Auto Pistol 320SXG5-9-STAS Buy Sig SAUER 1911XR-45-SS 45 ACP 5" Stainless Semi-Auto Pistol 8+1 Capacity online Sig SAUER 1911XR-45-SS 45 ACP 5" Stainless Semi-Auto Pistol 8+1 Capacity Buy Sig Sauer MCX Spear 762NATO 16" Barrel Multicam Cerakote M-LOK Ambi Controls online Sig Sauer MCX Spear 762NATO 16" Barrel Multicam Cerakote M-LOK Ambi Controls Buy Sig Sauer WM18-9-PRO-RM17 M18 9mm 3.9" Coyote Semi-Auto Pistol online Sig Sauer WM18-9-PRO-RM17 M18 9mm 3.9" Coyote Semi-Auto Pistol Buy Sig Sauer WM18-9-PRO-BLK-RM17 M18 9mm 3.9" Black Semi-Auto Pistol online Sig Sauer WM18-9-PRO-BLK-RM17 M18 9mm 3.9" Black Semi-Auto Pistol Buy Sig Sauer M17X 9mm 4.7in Coyote 21rd online Sig Sauer M17X 9mm 4.7in Coyote 21rd Buy Sig Sauer P320-M17 9mm 4.7in 3x10rd Coyote Tan online Sig Sauer P320-M17 9mm 4.7in 3x10rd Coyote Tan Buy Sig Sauer W1911XR-45-BXR3 1911 X Series .45 ACP 5" Black DLC Pistol online Sig Sauer W1911XR-45-BXR3 1911 X Series .45 ACP 5" Black DLC Pistol Buy Sig Sauer W1911XCA-45-BXR3 1911 X Carry 45 ACP 4.25" Black DLC Pistol online Sig Sauer W1911XCA-45-BXR3 1911 X Carry 45 ACP 4.25" Black DLC Pistol

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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