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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
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Founded
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All SI Products (2,384)

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 Buy Sig SAUER Juliet5-Micro 5x24mm Black Magnifier (SOJ5M001) online Sig SAUER Juliet5-Micro 5x24mm Black Magnifier (SOJ5M001) Buy Sig SAUER P365 Custom Works Fire Control Unit 9/380 Flat Blade Gold Frame online Sig SAUER P365 Custom Works Fire Control Unit 9/380 Flat Blade Gold Frame Buy Sig Sauer P365XL 8900777 9mm Luger 3.7" Gold Barrel w/LCI Non-Threaded online Sig Sauer P365XL 8900777 9mm Luger 3.7" Gold Barrel w/LCI Non-Threaded Buy Sig Sauer P365 9mm Luger 3.10" Gold Titanium Nitride Loaded Chamber Indi... online Sig Sauer P365 9mm Luger 3.10" Gold Titanium Nitride Loaded Chamber Indi... Buy Sig Sauer 8900763 LXG Grip Module Laser Engraved 9mm Luger P365XL Black online Sig Sauer 8900763 LXG Grip Module Laser Engraved 9mm Luger P365XL Black Buy Sig Sauer 8900758 P322 Ambidextrous IWB-OWB Black Composite Belt Clip F... online Sig Sauer 8900758 P322 Ambidextrous IWB-OWB Black Composite Belt Clip F... Buy Sig Sauer P365XL Barrel 9mm Luger 3.7 in Black Nitron Action Type online Sig Sauer P365XL Barrel 9mm Luger 3.7 in Black Nitron Action Type Buy Sig SAUER P322 22 LR 25rd Polymer Black Magazine (8900746) online Sig SAUER P322 22 LR 25rd Polymer Black Magazine (8900746) Buy Sig SAUER P322 22 LR 20rd Polymer Black Magazine (8900745) online Sig SAUER P322 22 LR 20rd Polymer Black Magazine (8900745) Buy Sig Sauer P320-XTEN 10mm Auto 15-Round Factory Magazine online Sig Sauer P320-XTEN 10mm Auto 15-Round Factory Magazine Buy Sig Sauer Clutch-Lok QD Muzzle Brake Stainless Steel 5-8" 24 TPI for 7.62mm online Sig Sauer Clutch-Lok QD Muzzle Brake Stainless Steel 5-8" 24 TPI for 7.62mm Buy Sig Sauer SL76258X2425DEGM Clutch-Lok QD Muzzle Brake 7.62mm Black online Sig Sauer SL76258X2425DEGM Clutch-Lok QD Muzzle Brake 7.62mm Black Buy Sig Sauer Clutch-Lok QD Muzzle Brake 5.56mm 90 Degree Taper online Sig Sauer Clutch-Lok QD Muzzle Brake 5.56mm 90 Degree Taper Buy Sig Sauer Clutch-Lok QD Muzzle Brake 5.56mm 25 Degree Taper online Sig Sauer Clutch-Lok QD Muzzle Brake 5.56mm 25 Degree Taper Buy Sig Sauer Clutch-Lok QD Flash Hider Stainless Steel 5-8" 24 tpi Threads ... online Sig Sauer Clutch-Lok QD Flash Hider Stainless Steel 5-8" 24 tpi Threads ... Buy Sig Sauer SL-762-58X24-25DEG-F Flash Hider 7.62MM 25 Degree Taper online Sig Sauer SL-762-58X24-25DEG-F Flash Hider 7.62MM 25 Degree Taper Buy Sig SAUER Clutch-Lok QD 5.56mm 90-Degree Shoulder Flash Hider online Sig SAUER Clutch-Lok QD 5.56mm 90-Degree Shoulder Flash Hider Buy Sig Sauer Clutch-Lok QD Flash Hider 5.56mm Black Stainless Steel 2.10" OAL online Sig Sauer Clutch-Lok QD Flash Hider 5.56mm Black Stainless Steel 2.10" OAL Buy Sig Sauer Tango-MSR LPVO 1-8x24mm Red Illuminated BDC8 Reticle online Sig Sauer Tango-MSR LPVO 1-8x24mm Red Illuminated BDC8 Reticle Buy Sig Sauer SOTM61001 Tango MSR 1-6x24 30MM Hellfire Reticle Scope online Sig Sauer SOTM61001 Tango MSR 1-6x24 30MM Hellfire Reticle Scope Buy Sig SAUER Tango MSR Scope 1-10X28mm 34mm SFP Illum BDC10 Reticle SOTM11000 online Sig SAUER Tango MSR Scope 1-10X28mm 34mm SFP Illum BDC10 Reticle SOTM11000 Buy SIG Sauer Alpha Cantilever Mount 34mm Tube Steel Alloy online SIG Sauer Alpha Cantilever Mount 34mm Tube Steel Alloy Buy Sig SAUER Alpha Cantilever Mount 30mm Tube Black Steel Alloy online Sig SAUER Alpha Cantilever Mount 30mm Tube Black Steel Alloy Buy Sig Sauer RomeoZero Mounting Kit for Hellcat/Glock 43x online Sig Sauer RomeoZero Mounting Kit for Hellcat/Glock 43x Buy Sig Sauer SOR0SK001 RomeoZero Shroud Kit Black for P365X/XL Handgun online Sig Sauer SOR0SK001 RomeoZero Shroud Kit Black for P365X/XL Handgun Buy Sig SAUER .380 Auto For P365 Microcompact 12rd Black Magazine (8900716) online Sig SAUER .380 Auto For P365 Microcompact 12rd Black Magazine (8900716) Buy Sig SAUER .380 Auto f/P365 Microcompact 10rd Finger Extension Blk Magazine online Sig SAUER .380 Auto f/P365 Microcompact 10rd Finger Extension Blk Magazine Buy Sig Sauer P365 Flush Magazine .380 ACP 10-Round Black online Sig Sauer P365 Flush Magazine .380 ACP 10-Round Black Buy Sig Sauer WRM400-556N-16B-PRO M400 Pro 223/5.56 16" Black Rifle online Sig Sauer WRM400-556N-16B-PRO M400 Pro 223/5.56 16" Black Rifle Buy Sig Sauer WRM400-556N-14B-PRO-SBR M400 SBR 223/5.56 14.5" Black Rifle online Sig Sauer WRM400-556N-14B-PRO-SBR M400 SBR 223/5.56 14.5" Black Rifle Buy Sig Sauer WRM400-556N-11B-PRO-SBR M400 SBR 223/5.56 11.5" Black Rifle online Sig Sauer WRM400-556N-11B-PRO-SBR M400 SBR 223/5.56 11.5" Black Rifle Buy Sig Sauer 8900696 Tread M400 Two-Stage Trigger Kit 5 lb Pull online Sig Sauer 8900696 Tread M400 Two-Stage Trigger Kit 5 lb Pull Buy Sig Sauer P320 X-Carry Legion Double Action Only Semi-Automatic Pistol 9mm online Sig Sauer P320 X-Carry Legion Double Action Only Semi-Automatic Pistol 9mm Buy Sig Sauer Airsoft P365 Magazine Black 6mm BB 12/Rd online Sig Sauer Airsoft P365 Magazine Black 6mm BB 12/Rd Buy Sig Sauer P365XL Recoil Spring Assembly 9mm Compatible with P365-XMACRO online Sig Sauer P365XL Recoil Spring Assembly 9mm Compatible with P365-XMACRO Buy Sig Sauer 8900674 TXG Grip Module P320 X-Carry 9/40/357 Gray online Sig Sauer 8900674 TXG Grip Module P320 X-Carry 9/40/357 Gray Buy Sig Sauer BuckMaster 3-12x44 Rifle Scope Hellfire BDC Reticle Waterproof online Sig Sauer BuckMaster 3-12x44 Rifle Scope Hellfire BDC Reticle Waterproof Buy Sig Sauer Juliet3-Micro Magnifier 3x22mm FDE online Sig Sauer Juliet3-Micro Magnifier 3x22mm FDE Buy Sig P320 XTEN 10mm Auto Pistol Black 5" Optic Ready online Sig P320 XTEN 10mm Auto Pistol Black 5" Optic Ready Buy Sig Sauer AIRP320XCABB CO2 Air Pistol 4.5" Barrel 350 fps 21rd Magazine online Sig Sauer AIRP320XCABB CO2 Air Pistol 4.5" Barrel 350 fps 21rd Magazine Buy Sig Air-1911es-bb .177bb Emperor Scorpion Co2 online Sig Air-1911es-bb .177bb Emperor Scorpion Co2 Buy Sig Sauer Buckmasters 3-12x44mm Rifle Scope 1" Tube BDC Reticle online Sig Sauer Buckmasters 3-12x44mm Rifle Scope 1" Tube BDC Reticle Buy Sig SAUER Buckmasters 3-9x50mm 1in SFP BDC Reticle Riflescope SOBM33002 online Sig SAUER Buckmasters 3-9x50mm 1in SFP BDC Reticle Riflescope SOBM33002 Buy Sig SAUER Buckmasters Rifle Scope 3-9x40mm BDC Reticle Black online Sig SAUER Buckmasters Rifle Scope 3-9x40mm BDC Reticle Black Buy Sig Sauer W320AXGF-9-BXR3-R2 P320 AXG 9mm 4.7" Nitron Semi-Auto Pistol online Sig Sauer W320AXGF-9-BXR3-R2 P320 AXG 9mm 4.7" Nitron Semi-Auto 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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