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SI designs rugged, user-focused firearm components and optics. They make accessories like slide plates, charging handles, barrel clamps, red dots, and shotgun parts.
All SI Products (2,384)
Sig P365X Texas Ranger 9mm 3.1" XRay-3 Optic Ready
Sig Sauer SOFEF001 Foxtrot-EDC Flashlight 1350 Lumens Black Aluminum
Sig Sauer SOFEC001 Foxtrot-EDC Flashlight 1350 Lumens Black Anodized
Sig Sauer 8901443 P365-XMACRO 9mm Caliber Exchange Kit 17+1 Black Slide
SIG Sauer P365XL Rose Comp 9mm 3.1" Pistol Kit
Sig Sauer P365 Rose Semi-Automatic Pistol .380 ACP
Sig Sauer 8901442 P365XL 9mm Black Nitron 12rd Magazine X-CHANGE Kit
Sig Sauer SOF2R100 Foxtrot2R 700 Lumens Black Anodized Tactical Light
Sig Sauer SOZ10004 Zulu10 HDX 15x56mm Binoculars Coyote Rubber Armor
Sig Sauer Zulu10 HDX 12x50 Binocular - Flat Dark E
Sig Sauer SOZ10001 Zulu10 HDX 10x42mm Binoculars, Coyote Rubber Armor
Sig Sauer AXG Legion Semi-Automatic Pistol 9mm Luger
Sig Sauer 8901427 Safety Parts Kit 9mm Luger/380 ACP Sig P365/P365X/XL Black
Sig Sauer 365X-9-RBT-MS 9MM Pistol 12+1 Rainbow Titanium X-Ray Sights
Sig Sauer 8901412 MCX/MPX Folding Stock Black Aluminum Locking Hinge
Sig Sauer 8901411 Minimalist Plus Black Aluminum Folding Stock 9" OAL
Sig SAUER Minimalist Locking Black Folding Stock for MCX/MPX (8901410)
Sig Sauer 8901360 Cross .308 Win 16" Stainless Rifle
SIG Sauer 8901359 Cross 6.5 Creedmoor 18" Stainless Barrel Kit
SIG Sauer P320 Spectre Comp 9mm 4.6" Blackout
Sig SAUER Canyon 19x42mm Rangefinder Binocular (SOKCN101)
SIG SAUER Tango-MSR 1-10x26mm Rifle Scope Coyote
Sig Sauer SOA20017 TANGO MSR Scope Mount 34MM 1.535 Coyote
Sig Sauer SOA20016 TANGO MSR Scope Mount 30MM 1.535" Coyote Brown
Sig Sauer 8901335 Safety Parts Kit 9mm Luger/380 ACP Sig P365/P365X/XL Blue
Sig Sauer 8901329 Safety Parts Kit 9mm Luger/380 ACP Sig P365/P365X/XL
Sig Sauer P365X Controls Parts Kit Rose Gold Matte Flat Trigger Slide Ca...
Sig Sauer 8901331 Safety Parts Kit 9mm Luger/380 ACP Sig P365/P365X/XL Rose Gold
Sig Sauer 8901330 Safety Parts Kit 9mm Luger/380 ACP Sig P365/P365X/XL Rainbow
Sig Sauer 8901327 Safety Parts Kit 9mm Luger/380 ACP Sig P365/P365X/XL
Sig Sauer 8901305 Safety Parts Kit 9mm Luger/380 ACP Sig P365/P365X/XL Nickel
Sig Sauer P226 XFive STAS 9MM 5in Stainless Steel 10rd Semi-Auto
Sig Sauer P226 X-Five Classic 9MM 5in Stainless Steel 10rd Semi-Auto
Sig Sauer Tango6T DVO 1-6x24mm FFP Rifle Scope FDE
Sig SAUER T300 Smart Target 5 Zone 5x3in Black Control Module (SC-T300)
Sig Sauer Tango-MSR 1-8x24mm Coyote Rifle Scope
Sig Sauer Tango MSR LPVO Rifle Scope 1-6x24mm Coyote
Sig SAUER TANGO-MSR LPVO 1-10x28 34mm SFP MSR BDC10 Riflescope SOTM11200
Sig Sauer 8901268 Minimalist Plus Coyote Brown Aluminum Folding Stock
Sig Sauer MCX MPX Skeletonized Stock Riser Cheek
Sig Sauer Barrel & Gas Block Assembly MCX 5.56 16
Sig Sauer SOFR1FS0 Foxtrot-MSR 1350 Lumen Weapon Light Black Aluminum
Sig Sauer SOFR1CM0 Foxtrot-MSR 1350 Lumen Weapon Light, Black Aluminum
Sig Sauer P365-XMACRO OWB Holster, Left Hand, Black
Sig Sauer P365-XMACRO OWB Holster Black Right Hand Thermal Plastic
Sig Sauer P365-XMACRO IWB Holster, Black, Left Hand
Sig Sauer 8901243 Blackpoint Tactical OWB Holster Coyote Tan Right Hand
Sig SAUER P229 Legion 9mm 3.9in X-Ray 3x10rd Cerakote Elite Gray Pistol
About SI
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.
Hot SI Items June 2026
Trending right now based on the last 30 days of TheGunDock orders + page views.
SIG SAUER 322C-ROSE-RS P322 Rose 22 LR 4" Black Anodize Semi
SilencerCo Sparrow 22 Rimfire Suppressor 22LR 5.08" Stainles
Sig Sauer W365XL-9-BXR3P-MS P365 XL 9mm 3.7" Nitron Semi-Aut
Sig Sauer Tango-MRS Compact Rifle Scope 1-6x24 30mm SFP BDC6
Sig Sauer Cross Sawtooth Rifle 6.5 PRC 22 inch Moss Green Fo
Sierra Bullets 4540C 7mm 0.284 Caliber 140 Grain Tipped Boat
SilencerCo AC1278 ASR Black Nitride 9/16"x24 LH Threads 30 C
Sig Sauer W365XL-9-BXR3P-RXX P365 XL Romeo-X 9mm 3.7" Nitron
Shop SI Products
Sig SAUER MCX-SPEAR 6.8x51mm SBR 13in Semi-Auto Rifle RSPEAR
SilencerCo Sparrow 22 Rimfire Suppressor 22LR 5.08" Stainles
Sig Sauer P320 FLUX 9MM 3.9" 30RD Legion 320
Sig Sauer SLH300TIQD 300 Blackout Titanium Suppressor
SilencerCo Velos LBP 5.56 NATO/.223 4.76 In Low Back-Pressur
SIG SAUER MCX Spear SBR 7.62x51mm 13" Nitride NFA
Sig Sauer P365X Macro Tacops 9mm 3.7" 17rd Pistol
Sinclair INTERNATIONAL DIAL INDICATOR .001
Sig Sauer ROMEO1 Black Shroud Kit SOR1SK001: Medium Size, Ne
Sig Sauer 8900823 LTXG Grip Module Laser Engraved P320-X Car
Sig Sauer MCX-SPEAR LT AR Conversion Kit 5.56 NATO 11.5" Bla
Sig SAUER MCX 5.56 NATO 16in 30rd IR Cerakote FDE Rifle RMCX
SI News & Articles
Firearm Shipping Restrictions by State (2026 Update)
State-by-state guide to firearm and ammunition shipping for online buyers and FFL dealers. Current as of May 2026. Cover...
Damaged in Transit: How TheGunDock Handles Shipping Claims on Firearms and Ammo
When a firearm or ammo shipment arrives damaged, the claim process matters. TheGunDock walks through what to do, what we...
The Springfield KUNA: Roller-Delayed 9mm Pistol That's Shaking Up the PDW Market
The Springfield Armory KUNA — a roller-delayed 9mm pistol built in partnership with Croatia's HS Produkt — has becom...
The Strait of Hormuz: 2,500 Years of Trade, Arms, and Conflict
A twenty-one-mile-wide choke point has shaped the movement of goods — and weapons — across half the ancient and mode...
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