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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 (2,381)
Sig Sauer P365 Sub-Compact Grip Module, Gray, Manual Thumb Safety, 8900328
Sig Sauer 8900315 P320 9mm 5.5" Threaded Barrel Black Nitride Finish
Sig Sauer Universal Offset Mount Black Anodized 45 Degree MSR
Sig SAUER Custom Works P320 Fire Control Unit (8900160)
Sig SAUER P320 AXG Carry Medium 9/40/357 Black Panels/Blk Grip Module Assy
Sig SAUER P320 XFive TXG Caliber X-Change Kit (8900269)
Sig Sauer 8900282 9MM Luger 4.7 In Coyote ROMEO1 PRO 6MOA
Sig Sauer P320 Grip Module X-Series TXG Large Gray Polymer 9mm 40 S&W 35...
Sig SAUER TXG P320 9/40/357 Full Size Small Gray Grip Module (8900273)
Sig Sauer M320/M18 9mm Coyote X-Change Kit 3 Magazines
Sig SAUER P320 9mm Caliber X-Change Kit - Coyote 8900267 Accessory
SIG SAUER 9mm 10rd Flush Magazine For P365XL (8900250)
Sig Sauer Easy6-BDX 5-30x56mm Rifle Scope Black
Sig Sauer Bravo6T-BDX Rifle Scope 5-30x56mm 35mm FFP MRAD Milling 2.0 Illum Black
Sig SAUER Easy6-BDX 3-18x44mm Rifle Scope Black
Sig Sauer Bravo6T-BDX Rifle Scope 3-18x44mm 35mm FFP MRAD DEV-L 2.0 Illum Black
Sig SAUER Easy6-BDX 1-6x24mm BDX-R2 Reticle Riflescope (SOEBDX61101)
Sig Sauer SLH762CQD Compact 7.62mm Suppressor
Sig Sauer SLX556CQD Compact 5.56mm Suppressor
Sig Sauer SLX762QD SLX 7.62mm 1.67" D, 7.40" L Black Inconel
SIGA SLX556QD 5.56mm Suppressor, 7.40" Length, 1.67" Diameter
Sig Sauer W320F-9-BXR3-TXG-PRO P320 9mm 4.7" Nitron Semi-Auto Pistol
Sig Sauer W320F-9-BXR3-LDC-PRO P320 9mm 4.7" Nitron Semi-Auto Pistol
Sig Sauer KILO5K 7x25 Digital Ballistic Laser Rangefinder Green
Sig Sauer Sierra6 BDX 5-30x56mm Rifle Scope 34mm Tube Black BDX-R2 MOA
SIG SAUER Sierra6BDX 3-18x44mm Rifle Scope 30mm Tube Black BDX-R2 Reticle
Sig Sauer Electro-Optics Sierra6BDX 2-12x40mm Black Anodized Rifle Scope
Sig Sauer SOEC32001 ECHO3 Thermal Reflex Sight 2-12X M1913 Nightvision
Sig Sauer P320F 9/40 Small Coyote Grip Module
Sig Sauer P320F 9/40 Medium Coyote Grip Module
Sig Sauer P320 Compact Grip Module Coyote Tan
SIG Sauer P320 Carry Grip Module 9/40/357 Manual Safety Black
Sig Sauer P320 8900190 M17 9mm Luger Recoil Spring Assembly
Sig Sauer AIR-PF-M18GG Proforce M18 Airsoft 6mm Green Gas Coyote Tan
Sig Sauer AMPF-M18GG 6mm 21-Round Green Gas Airgun Magazine
Sig SAUER Custom Works Black Fire Control Unit for P320 Pistol (8900161)
Sig Sauer SOR91002 Romeo9T Red/Green Dot Sight Flat Dark Earth 1x38mm
Sig Sauer CROSS6518B Cross 6.5 Creedmoor Bolt-Action Rifle 18" Black
Sig Sauer Cross PRS 308 Win Bolt Action Rifle 24" Barrel Concrete Cerakote Metal Finish
Sig Sauer CROSS .308 Win 16" 5-Rounds
Sig Sauer 8900157 P365 Grip Module 9MM Luger Coyote Polymer Fits (Manual
Sig Sauer 8900156 Grip Module Assembly P365 9mm Manual Safety Black
Sig Sauer P365 9mm Grip Module Coyote Tan Assembly
Sig Sauer SOR91001 Romeo9T Red/Green Dot Sight 1x38mm Black
Sig SAUER X-Series Full Size 9/40/357 Medium Coyote Tan Grip Module f/ P320
Sig Sauer Recoil Spring 40 S&W 357 P229 Flat Wire Steel
Sig Sauer P320 Enhanced Flat Trigger Black Stainless Steel
Sig Sauer P365 Disconnector Handgun Action Component Performance Upgrade
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.
SilencerCo Sparrow 22 Rimfire Suppressor 22LR 5.08" Stainles
SIG SAUER 322C-ROSE-RS P322 Rose 22 LR 4" Black Anodize Semi
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
Sig Sauer W365XL-9-BXR3P-MS P365 XL 9mm 3.7" Nitron Semi-Aut
Sig Sauer 2401191R Picatinny Stock Adapter for AR-15, Alumin
Sig Sauer SORX1080 24MM Black Pro Optics Ready Sight
SIG SAUER E26R-9-BSS-FBZ P226 Full-Size 9mm 4.4" 2-Tone Bron
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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