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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 Echo3 Thermal Reflex Sight 1-6x23mm Black
Sig Sauer P320 Grip Module 9mm 40 S&W 357 SIG Coyote Tan Medium
SIG Sauer P320 Grip Module: Coyote Finish, 9/40/357, Medium Size
SIG Sauer P320 X-Series Medium Coyote Grip Module Upgrade 9/40
Sig Sauer Elite Hunter Tipped 6mm Creedmoor 100 gr CET Ammo
Sig Sauer 8900062 P365XL Grip Module 9mm Black Polymer
Sig Sauer E270TH220 Elite Hunter Tipped 270 Win 140 gr 2950 fps CET 20 Bx
Sig Sauer P320 X-Five Legion 9mm 10-Round Magazine
Sig SAUER 9mm 17rd Magazine For P320 X-FIVE Legion (8900060)
Sig Sauer E65CMTH120 Elite Hunter Tipped 6.5 Creedmoor 130 gr 2850 fps Controlled Expansion Tip (CET) 20 Bx
Sig Sauer Elite Hunter Tipped 30-06 Springfield 165 gr 2950 fps CET 20 Bx
Sig SAUER P365/X/XL 9mm Luger 12rd Coyote Magazine (MAG-365-9-12-COY)
Sig SAUER 9mm 10rd Finger Extension Coyote Magazine For P365 Subcompact
Sig Sauer MAG365910COY P365 9mm 10rd Coyote Brown Steel Magazine
Sig Sauer P320 X-Series TXG Grip Module 9mm 4.70in Tungsten Polymer
Sig Sauer P320X5 TXG Grip Module Kit Gray
SIG Sauer Grip Module Assembly P320 Manual Safety 9mm/.40 S&W Small Black
Sig Sauer P320 Carry Grip Module Assembly - Medium, Black
Sig Sauer 8900032 MCX 7.62x39 28-Round Black Steel Magazine
Sig Sauer SOR3M100 Romeo03 Max XL Mount Absolute Co-Witness
Sig Sauer P320 XFive Legion 9mm Pistol Stainless 5" Barrel TXG Grip 10rd
Sig Sauer P320 X-five Legion 9mm 17 + 5" barrel
Sig Sauer 8900008 30-Round AR-15 Magazine 5.56 NATO Black Polymer
Sig Sauer Romeo1Pro 1x30mm Red Dot Sight 6 MOA FDE
Sig Sauer P238 380 ACP 2.7" Barrel 6+1 CA Compliant Black Stainless
Sig Sauer P320 X-Series Grip Module Small 9mm 40 S&W 357 Coyote Polymer
Sig Sauer GRIPMODXF943SMBLK P320 X-Series Grip Module Small Black Polymer
Sig Sauer GRIPMODXF943LGCOY P320 X-Series Large Coyote Grip Module
Sig Sauer P320 Grip Module X-Series Large Size Fits Full 9mm 40 S&W...
Sig Sauer GRIPMODXCA943SMCOY P320 X-Series Carry Grip Module Coyote Tan
Sig Sauer GRIPMODXCA943SMBLK P320 X-Series Carry Grip Module Black Polymer
Sig SAUER P320 X-Series Carry 9/40/357 Large Black Grip Module Assy
SIG SAUER Romeo1 Pro 6 MOA Dot Black Red Sight (SOR1P101)
Sig Sauer Romeo1Pro Black 1x30mm 3 MOA Red Dot Sight
SIG SAUER Alpha1 Hunting Scope Ring Set 35mm Extra High Matte Black
SIG SAUER Alpha1 Hunting Rifle Scope Rings 35mm High Matte Black
Sig SAUER Alpha1 Hunting Scope Ring Set 35mm Medium Black
Sig SAUER Alpha1 1in Extra High 1.25in Aluminum Matte Black Scope Rings
SIG SAUER Alpha1 1in Medium Aluminum Black Hunting Scope Rings (SOA10020)
Sig Sauer SOA10019 Alpha 1 1 inch Low Scope Ring Set Matte Black Aluminum
SIG Sauer Alpha1 34mm X-High Tactical Mount
Sig Sauer P938 Micro-Compact Legion 9mm Luger 3" 10+1 Gray Cerakote Stainless Steel Black G10 Grip X-Ray3 Night Sight
Sig Sauer Airguns AIRAMMOVPB22 Venom 22 Lead 250/Tin
Sig Sauer Airguns AIRAMMODPB22 Dagger 22 Lead 250/Tin
Sig Sauer Airguns AIRAMMODPB177 Dagger 177 Lead 500/Tin
Sig Sauer AIR-S1-MPX-S Airsoft Rifle, Spring, 6mm BB, Adjustable Stock
SIG Sauer Elite Hunting Copper 6mm Creedmoor Ammo 80gr
SIG SAUER BR6MMCM 6mm Creedmoor Brass 50/Bag
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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Choose SI for straightforward, well-engineered accessories that improve usability and durability without unnecessary complexity....
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