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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 Sauer AIRP320SC177BLK 177 Optics Ready Black Tactical
Sig Sauer SOA55005 35mm 1.535 Alpha5 Scope Mount
Sig Sauer SOA55004 35mm Alpha5 Scope Mount Tactical
Sig Sauer SOA54005 34mm Optics Ready Scope Mount
Sig Sauer SOA54004 34mm Alpha5 Scope Mount Tactical
Sig Sauer P365 Fuse 9mm 4.3in Optic Ready 21RD Semi-Auto Pistol
Sig Sauer MH68MM113B920 Hybrid 6.8mm 113gr 920rnds *Crate
Sig Sauer 4204140R MCXSPEAR Long Stroke Piston Tactical
Sig Sauer P365X Full Size Rose Gold Handgun 9mm Luger 12rd Magazines (2) 3.1 Barrel Black
Sig Sauer P365 XMacro Handgun 9mm Luger 17rd Magazines (2) 3.7 Barrel Two Tone Green TB
Sig Sauer P365 XMacro Handgun 9mm Luger 17rd Magazines (2) 3.7 Barrel Two Tone Green TB with Optic
Sig Sauer P365 XMacro Handgun 9mm Luger 17rd Magazines (2) 3.7 Barrel Two Tone Tan TB
Sig Sauer P365X 9mm 12Rd Night Sights Optics Ready
Sig Sauer M18 9mm 21Rd Night Sights Coyote Pistol
Sig Sauer M17 9mm 21Rd Night Sights Coyote 4.7in
Sig Sauer P320 9mm 17Rd Night Sights Optics Ready
Sig Sauer W320C 9mm 15Rd Night Sights Optics Ready
SIMUNITION 8971835 Womens Lightweight Protective Vest
SIG SAUER P320 COMPACT HGA 9MM 3.9IN BBL SIGLITE COYOTE MOD PLY GRIP 3 15RD MAG
Sig Sauer 320C9BSSMS P320 Compact 9mm Luger 3.90" 15+1 Black Polymer Grip Black Nitron Stainless Steel
Sight SM17005 3.5-28X30 Thermal Scope Optics Ready
Sight SM17004 Thermal Optics Ready 2 16X15 Premium
Sig Sauer P320 P320 9mm Luger Long Dust Cover 17+1 4.700 Black
Sig Sauer P320 P320 9mm Luger 17+1 4.700 Black
Sig Sauer P365X M81 Metal Comp Handgun 9mm Luger 17rd Magazine 3.5 Comp Barrel Metal Grip
Sight SM23002 Strikon 1x18 Tactical Optics Ready
Sight SM23001 Strikon VMP 1-4x22 Tactical Optic
Sight SM13144CRE 1-10X26 Tactical Optics Ready Scope
Sig Sauer P365 Fuse Semi-automatic Striker Fired Polymer Frame Pistol
Sig Sauer MPX Semi-automatic Short Barreled Rifle 9MM 6" Barrel Matte
Sig Sauer P365X 380 3.1" Barrel 10-Round Compensator
Sig Sauer P365XF Semi-automatic Striker Fired Polymer Frame Pistol Compact
Sig Sauer P365XF Semi-automatic Striker Fired Polymer Frame Pistol Compact
Sig Sauer P365XF Semi-automatic Striker Fired Polymer Frame Pistol Compact
SIG SAUER 211F-9-GT5-RXSL P211-GT5 9mm 5" Bull Barrel Nitron Semi-Auto Pistol
SIG SAUER 211F-9-GT5-COY P211-GT5 9mm 5" Bull Barrel Coyote Cerakote Semi-Auto Pistol
SIG SAUER 211F-9-GT5-10 P211-GT5 9mm 5" Bull Barrel Nitron Semi-Auto Pistol
SIG SAUER 211CA-9-GT4-RXSL P211-GT4 9mm 4.2" Bull Barrel Nitron Semi-Auto Pistol
SIG SAUER 211CA-9-GT4-COY P211-GT4 9mm 4.2" Bull Barrel Coyote Cerakote Semi-Auto Pistol
SIG SAUER 211CA-9-GT4-10 P211-GT4 9mm 4.2" Bull Barrel Nitron Semi-Auto Pistol
SIG SAUER 211F-9-GT5 P211-GT5 9mm 5" Bull Barrel Nitron Semi-Auto Pistol
SIG SAUER 211CA-9-GT4 P211-GT4 9mm 4.2" Bull Barrel Nitron Semi-Auto Pistol
Sig Sauer P211 9mm 4.4" Barrel 21/23 Round Capacity
Sig Sauer Barrel 9MM 3.7" Threaded Barrel 1/2X28 Thread Pitch Fits Sig
Sig Sauer Barrel 9MM 3.7" Threaded Barrel 1/2X28 Thread Pitch Fits Sig
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 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
Sig Sauer 2401191R Picatinny Stock Adapter for AR-15, Alumin
Sig Sauer SORX1080 24MM Black Pro Optics Ready Sight
Sig Sauer W365XL-9-BXR3P-RXX P365 XL Romeo-X 9mm 3.7" Nitron
Sig SAUER 365XF-9-CFO-2A P365 Fuse 9mm 4.3" Nitron Semi-Auto
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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