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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 P320 Pro 9mm 15 Rounds with ROMEO-X Reflex Sight
Sig Sauer SOTS46000 TANGO 6-24x52 MOA BDC1 Reticle SFP Scope Black
Sig Sauer SOTS44000 TANGO 4-16x44 MOA BDC1 Reticle SFP Scope Black
Sig Sauer SOTS41000 TANGO 1-4x24 Hellfire SFP Scope Black
Sig Sauer Cross Sawtooth Rifle 6.5 PRC 22 inch Moss Green Folding Precis...
Sig Sauer WPMCX-762R-11B-LT-FDE MCX Rattler LT 7.62x39mm 11.5" FDE Pistol
Sig Sauer SOO62001 OSCAR6 HDX Pro 16-32x60mm Spotting Scope FDE Armor
Sig Sauer SOZ6B150 Zulu6 HDX Pro Binocular Adapter Arca Swiss Mount
Sig Sauer CROSS 6.5 Creedmoor Rifle 18" Carbon Fiber Barrel Moss Green
SIG Sauer CROSS 308 Rifle 5+1 16" Moss Green Folding Stock
Sig SAUER Marksman Hunter 6.5 Creedmoor 130Gr JHP 20Rd/Box Rifle Ammo
Sig Sauer P365 W365XCA9BXR3P 9mm 3.7" Black 17rd OR Pistol
Sig Sauer SOJ3MT01 Juliet 3 Magnifier 3x22mm CNC Aluminum Black
Sig Sauer WM18-9-PRO-BLK M18 9mm 3.9" Black Semi-Auto Pistol
Sig Sauer WM17-9-PRO-BLK P320 M17 9mm 4.7" Black Semi-Auto Pistol
Sig Sauer SORJMSR501 Romeo MSR Gen II 2 MOA Red Dot Juliet5 Combo
Sig SAUER Romeo-X Sig-Loc Compact 2 MOA Circle/Dot Reflex Sight (SORX1600)
Sig Sauer Cross 277 Fury Bolt Action Rifle 20" Barrel (1)5RD Mag Black
Sig SAUER Buckmasters 3-9x40mm 1" Second Focal Plane Riflescope (SOBM33004)
Sig SAUER SOZBH203 Zulu Binocular Harness & Pouch Medium Flat Dark Earth
SIG P365 XL 9MM 3.1" XRAY-3 OR 10RD Rose Kit Black CA Comp
Sig Sauer NG762SPEARQD 7.62mm Coyote Inconel 1.75"
SIG SAUER P320 XFIVE SXG Steel Frame Competition Pistol 5 Bull Barrel
Sig Sauer P320-Max SXG Handgun 9mm Luger 10rd Magazines(4) 5 Barrel Romeo3 Max 6 MOA
Sig Sauer P320-Max SXG Handgun 9mm Luger 21rd Magazines(4) 5 Barrel Romeo3 Max 6 MOA
Sig Sauer P320-Max 2.0 Handgun 9mm Luger 10rd Magazines(4) 5 Barrel Romeo3 Max 6 MOA
Sig Sauer P320-Max 2.0 Handgun 9mm Luger 21rd Magazines(4) 5 Barrel Romeo3 Max 6 MOA
SIG SAUER SOR02130 Romeo-RS 3 MOA Red Dot Sight Black Compact
SIG SAUER SOR02030 Romeo-RS 3 MOA Red Dot Sight Black Pro Footprint
Sig SAUER Platinum Hunter 6.5Crdmr 140Gr Nosler Accubond Ammo E65CMPH140-20
Sig SAUER Platinum Hunter 308 Win 165Gr Nosler Accubond Ammo (E308PH165-20)
Sig Sauer E3006GK16520 Marksman Hunter 30-06 Springfield 165gr 20 Rounds
Sig Sauer E7RMPH16020 Platinum Hunter 7mm Rem 160gr 20 Rounds
Sig Sauer E3WMPH18020 Platinum Hunter 300WM 180gr 20/Box
Sig Sauer E3006PH18020 Platinum Hunter 30-06 Springfield 180gr 20/Box
Sig Sauer E270PH15020 Platinum Hunter 270 Win 150gr 20/Box
Sig Sauer E243PH9020 Platinum Hunter 243 Win 90gr 20/Box
Sig Sauer E7RMGK16020 Marksman Hunter 7mmRem 160Gr
Sig Sauer E3WMGK16520 Marksman Hunter 300WM 165gr 20rd Box
Sig Sauer E270GK14020 Marksman Hunter 270 Win 140gr 20/Box
Sig Sauer E308GK16520 Marksman Hunter 308 Win 165gr 20/Box
Sig Sauer E243GK8520 Marksman Hunter 243 Win 85gr 20/Box
Sig Sauer SOEC42320 Echo MV50-DV Thermal Monocular 1.5-24x50mm 640x512
Sig Sauer SOEC42310 Echo MV50-LRF Thermal Monocular 3-24x50mm 640x512 50Hz
Sig Sauer SOEC42200 Echo Thermal Monocular 2-16x35mm 640x512 50Hz IP67
Sig Sauer MH68MM113B920 Hybrid 6.8mm 113gr 920rnds *Crate
Sig Sauer MH68MM113B-460 6.8mm 113gr Hybrid Ball Ammo Can 460-Round
Sig Sauer P320 Full .40 S&W 14+1 Capacity Striker-Fired with ROMEO-X Ref...
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 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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Choose SI for straightforward, well-engineered accessories that improve usability and durability without unnecessary complexity....
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