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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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2,381
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Founded
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All SI Products (2,381)

Buy Sig Sauer 8900980 P365 Slide Completion Kit 9mm Corrosion Resistant online Sig Sauer 8900980 P365 Slide Completion Kit 9mm Corrosion Resistant Buy Sig Sauer 8900979 P320 Slide Parts Kit 9mm/357Sig Steel Components online Sig Sauer 8900979 P320 Slide Parts Kit 9mm/357Sig Steel Components Buy Sig Sauer P320 9mm Luger Coyote Brown Stainless Steel Optic Ready Slide online Sig Sauer P320 9mm Luger Coyote Brown Stainless Steel Optic Ready Slide Buy Sig Sauer 8900952 P320 Pro-Cut Slide 9mm Coyote Brown PVD XRAY3 Sights online Sig Sauer 8900952 P320 Pro-Cut Slide 9mm Coyote Brown PVD XRAY3 Sights Buy Sig Sauer 8900951 P320 Subcompact 9mm Pro-Cut Slide, Optic Ready, Coyote online Sig Sauer 8900951 P320 Subcompact 9mm Pro-Cut Slide, Optic Ready, Coyote Buy Sig Sauer 8900950 P320 9mm Optic Ready Slide Black PVD XRAY3 Sights online Sig Sauer 8900950 P320 9mm Optic Ready Slide Black PVD XRAY3 Sights Buy Sig Sauer 8900949 P320 9mm Optic Ready Slide Black PVD XRAY3 Sights online Sig Sauer 8900949 P320 9mm Optic Ready Slide Black PVD XRAY3 Sights Buy Sig Sauer 8900948 P320 9mm Optic Ready Slide Black PVD XRAY3 Sights online Sig Sauer 8900948 P320 9mm Optic Ready Slide Black PVD XRAY3 Sights Buy Sig Sauer M400 X-Series 5.56 NATO 16" 30+1 Black Magpul SL-K Stock Flat Match Trigger online Sig Sauer M400 X-Series 5.56 NATO 16" 30+1 Black Magpul SL-K Stock Flat Match Trigger Buy SIG SAUER Buckmaster 10x42mm Roof Prism Binoculars online SIG SAUER Buckmaster 10x42mm Roof Prism Binoculars Buy Sig Sauer 8900917 Safety Parts Kit 9mm Luger/380 ACP Sig P365/P365X/XL Gold online Sig Sauer 8900917 Safety Parts Kit 9mm Luger/380 ACP Sig P365/P365X/XL Gold Buy Sig Sauer P365XL 9mm 3.7in Barrel Black Manual Safety 10rd Capacity online Sig Sauer P365XL 9mm 3.7in Barrel Black Manual Safety 10rd Capacity Buy Sig Sauer P365 XL 9mm Luger Pistol 10 Rounds Black online Sig Sauer P365 XL 9mm Luger Pistol 10 Rounds Black Buy Sig Sauer P365X 9mm 3.1 in Barrel Black Manual Safety 10-Round online Sig Sauer P365X 9mm 3.1 in Barrel Black Manual Safety 10-Round Buy Sig Sauer P365X Micro-Compact 9mm Pistol with X-RAY3 Sights online Sig Sauer P365X Micro-Compact 9mm Pistol with X-RAY3 Sights Buy Sig Sauer P365X 9mm Luger Micro-Compact Pistol, 3.10" Barrel, Optic Ready/Serrated Slide, Black Frame, Polymer Grips online Sig Sauer P365X 9mm Luger Micro-Compact Pistol, 3.10" Barrel, Optic Ready/Serrated Slide, Black Frame, Polymer Grips Buy Sig Sauer P365X 9mm Luger Micro-Compact Pistol online Sig Sauer P365X 9mm Luger Micro-Compact Pistol Buy SIG SAUER P320 XFull 9mm 4.7" Barrel Black XRay3 Optic Ready online SIG SAUER P320 XFull 9mm 4.7" Barrel Black XRay3 Optic Ready Buy Sig Sauer P320 XFull 9MM 4.7in Barrel Stainless Steel 17rd Striker Fired online Sig Sauer P320 XFull 9MM 4.7in Barrel Stainless Steel 17rd Striker Fired Buy Sig Sauer P320 XCompact 9mm Luger 3.60" Barrel Black Optic Ready/Serrated Slide Stainless Frame XCompact Polymer Grips online Sig Sauer P320 XCompact 9mm Luger 3.60" Barrel Black Optic Ready/Serrated Slide Stainless Frame XCompact Polymer Grips Buy Sig Sauer P320 XCompact 9mm 3.6in Black 15rd Striker Fired Pistol online Sig Sauer P320 XCompact 9mm 3.6in Black 15rd Striker Fired Pistol Buy Sig SAUER Foxtrot365XR 550 Lumens Pistol Light (SOF365X1) online Sig SAUER Foxtrot365XR 550 Lumens Pistol Light (SOF365X1) Buy Sig SAUER P220 Legion Full 10mm 5in DA/SA X-RAY3 Day/Night Sight Pistol online Sig SAUER P220 Legion Full 10mm 5in DA/SA X-RAY3 Day/Night Sight Pistol Buy Sig Sauer P220 Legion SAO .45ACP 4.4" Gray G10 X-Ray3 8rd online Sig Sauer P220 Legion SAO .45ACP 4.4" Gray G10 X-Ray3 8rd Buy Sig Sauer P220 Legion Series Semi-Automatic Pistol .45 ACP online Sig Sauer P220 Legion Series Semi-Automatic Pistol .45 ACP Buy Sig Sauer P226 XFive 9mm 5in Bull Barrel Stainless 20rd Single Action online Sig Sauer P226 XFive 9mm 5in Bull Barrel Stainless 20rd Single Action Buy Sig Sauer P226X59CLASSIC 9mm SAO 5" SS Optic Cut Hogue Cocobolo Grip online Sig Sauer P226X59CLASSIC 9mm SAO 5" SS Optic Cut Hogue Cocobolo Grip Buy Sig Sauer Buckmaster 1" High Black Aluminum Hunting Scope Rings online Sig Sauer Buckmaster 1" High Black Aluminum Hunting Scope Rings Buy Sig SAUER Buckmasters 1in Medium 0.94in Matte Black Scope Rings (SOA10034) online Sig SAUER Buckmasters 1in Medium 0.94in Matte Black Scope Rings (SOA10034) Buy Sig Sauer Buckmaster 1" Low Scope Ring Set online Sig Sauer Buckmaster 1" Low Scope Ring Set Buy Sig Sauer Romeo2 Red Circle Dot Reflex Sight 1x30mm online Sig Sauer Romeo2 Red Circle Dot Reflex Sight 1x30mm Buy Sig MPX GEN II Air Rifle .177 Cal CO2 30rd Black online Sig MPX GEN II Air Rifle .177 Cal CO2 30rd Black Buy Sig SAUER MCX Gen 2 .177 Cal 17.7in 30rd Blk Air Rifle (AIR-MCX-177-G2-BLK) online Sig SAUER MCX Gen 2 .177 Cal 17.7in 30rd Blk Air Rifle (AIR-MCX-177-G2-BLK) Buy Sig Sauer 8900823 LTXG Grip Module Laser Engraved P320-X Carry Gray online Sig Sauer 8900823 LTXG Grip Module Laser Engraved P320-X Carry Gray Buy Sig Sauer P365AXG Legion 9MM 17-Round Magazine Black online Sig Sauer P365AXG Legion 9MM 17-Round Magazine Black Buy Sig Sauer KILO3K 6x22 Rangefinding Monocular OLED Display Green online Sig Sauer KILO3K 6x22 Rangefinding Monocular OLED Display Green Buy Sig Sauer SOR44002 ROMEO4XT-PRO 1x20mm Red Dot Sight FDE 0.5MOA M1913 online Sig Sauer SOR44002 ROMEO4XT-PRO 1x20mm Red Dot Sight FDE 0.5MOA M1913 Buy Sig Sauer SOR44001 Romeo4XT-Pro Red Dot Sight 1x20mm 0.5MOA Black online Sig Sauer SOR44001 Romeo4XT-Pro Red Dot Sight 1x20mm 0.5MOA Black Buy Sig SAUER SigMPX 9mm 20rd Thril Black Rifle Magazine (8900828) online Sig SAUER SigMPX 9mm 20rd Thril Black Rifle Magazine (8900828) Buy SIG Sauer 8900746 P322 .22 LR 10-Round Black Polymer Magazine online SIG Sauer 8900746 P322 .22 LR 10-Round Black Polymer Magazine Buy Sig MCX-SPEAR LT 7.62x39mm 16" 28rd Folding Stk M-LOK Coyote online Sig MCX-SPEAR LT 7.62x39mm 16" 28rd Folding Stk M-LOK Coyote Buy Sig Sauer SOR2M103 Universal Mount Low Profile Black Stainless Steel 6.3" online Sig Sauer SOR2M103 Universal Mount Low Profile Black Stainless Steel 6.3" Buy Sig Sauer P320 XCarry Medium Grip Module: Laser-Stippled, Polymer, Black online Sig Sauer P320 XCarry Medium Grip Module: Laser-Stippled, Polymer, Black Buy Sig Sauer P365 X-MACRO Magazine 9mm 17rd Blued Steel online Sig Sauer P365 X-MACRO Magazine 9mm 17rd Blued Steel Buy Sig Sauer SOR2M102 Romeo2 Adapter Plate Black Glock MOS Handgun online Sig Sauer SOR2M102 Romeo2 Adapter Plate Black Glock MOS Handgun Buy Sig Sauer 8900791 P320 9mm 4.7" Gold Nitride Barrel for Full-Size Models online Sig Sauer 8900791 P320 9mm 4.7" Gold Nitride Barrel for Full-Size Models Buy Sig Sauer P320 Compact 8900790 - 9mm Luger, 3.90" Barrel, Gold Titanium-Nitride Finish online Sig Sauer P320 Compact 8900790 - 9mm Luger, 3.90" Barrel, Gold Titanium-Nitride Finish Buy Sig Sauer 8900789 P320 Subcompact 9mm Luger 3.7" Gold Barrel Non-Threaded online Sig Sauer 8900789 P320 Subcompact 9mm Luger 3.7" Gold Barrel Non-Threaded

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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