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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 W365XL-9-BXR3P-MS P365 XL 9mm 3.7" Nitron Semi-Auto Pistol
Sig Sauer SOR5X201 ROMEO5XDR Gen 2 1x20mm Red Dot Sight 2 MOA Black
SIG SAUER P365XL Rose 9mm 3.1" Pistol
Sig SAUER M18X 9mm 3.9in 3x 21rd Mags Coyote Tan Pistol (M18X-9-RX)
Sig P365 9mm Micro-Compact 10+1 Capacity, XRAY3 Sights, 3.1" Barrel
Sig Sauer 8901484 Grip Module P320-X Compact Manual Safety Coyote 9/40/357
Sig Sauer 8901483 Grip Module P320-X Compact Manual Safety Black
Sig Sauer P320 M17 Grip Module 9/40/357 Manual Safety Black 8901482
Sig SAUER P320 Full Size 9/40/357 Manual Safety Medium Coyote Grip 8901481
Sig SAUER P320 Full Size 9/40/357 Manual Safety Medium Black Grip 8901480
Sig Sauer 8901479 Grip Module P320-Compact Manual Safety Black 9/40/357
Sig SAUER Manual Safety Medium Blk Grip Module Assembly f/Sig Sauer 8901478
SIG SAUER 938-9-RBT2-AMBI P938 9mm Rainbow Titanium 3" Semi-Auto Pistol
Sig SAUER P238 Micro-Compact 380 ACP 2.7in Siglite Sights 6rd SAO Pistol
Sig SAUER RMCX-556N-16B-LT-B MCX-LT 16" Rifle 223 Rem/5.56 NATO Nitride
SIG P320 Spectre Comp Blackout 9mm 4.6" XRay3 Day/Night Sights
Sig Sauer SOZ80001 Zulu8 HDX 10x42mm Binoculars, Coyote Rubber Armor
Sig Sauer MCX-SPEAR LT AR Conversion Kit 5.56 NATO 11.5" Black
Sig Sauer MCX-SPEAR LT AR Conversion Kit 300 Blackout 9" Black UAMCX-300B-9B-L
Sig Sauer 1911X 45AP 8+1 X-Ray3 Sights Coyote Tan PVD 5"
Sig Sauer 1911X 45AP 8+1 Black DLC X-Ray3 Sights G10 Grips 5" Barrel
Sig Sauer WPMCX-762R-11B-LT MCX Rattler LT 7.62x39mm 11.5" Black Pistol
Sig Sauer WPMCX-556N-9B-LT MCX Rattler LT 223/5.56 9" Black Pistol
Sig SAUER Whiskey4 5-20x50mm FFP Illuminated MOA Milling Hunter 2.0 Reticle
SIG SAUER Whiskey 4 5-20x50mm Rifle Scope FFP MOA Milling Hunter 2.0
Sig Sauer Whiskey 4 SOW44002 4-16x44mm 30mm FFP Illuminated Matte Black
SIG SAUER Whiskey 4 4-16x44mm Rifle Scope FFP MOA Milling
Sig Sauer Whiskey 4 SOW43002 3-12x44mm 30mm SFP Matte Black Scope
SIG SAUER Whiskey 4 3-12x44mm Rifle Scope BDC Black
SIG SAUER P365-XMacro 9mm Luger 10rd Black Pistol Magazine (8901466)
Sig Sauer 365XCA-9-COMP-10 P365X Macro Comp 9mm 3.1" Black 10-Rd
SIG P365XCA9BXR3MS10 9mm 3.7" 10+1 Black Optic-Ready Pistol
P365-XMACRO 9mm Compact Pistol 3.7" Barrel Optic Ready Slide
Sig SAUER Zulu Canyon Binoculars 10x42 FDE HD Glass Roof Prism IPX-7 Waterproof
Sig SAUER Tango6T 1-6x24 30mm SFP FL-6 Illum FDE Riflescope w/ Alpha4 Mount
Sig Sauer MCX Spear Pistol 7.62x51 13in Barrel Coyote 20rd Semi-Auto
Sig Sauer H277SFOTM15520 Fury 277 150gr 20/Box 3000fps 3097ft-lbs
Sig Sauer 8901458 MCX/MPX Coyote Brown Aluminum Folding Stock
Sig SOZT1002 ZULUDMR Carbon Fiber Tripod
Sig Sauer SOZB1002 Zulu Binocular Adapter, Flat Dark Earth, Aluminum
Sig Sauer P365 9mm 3.1 in Black Nitron 10 Round Semi-Auto Pistol
Sig Sauer P365-9-BXR3P 9mm 3.1in Black Nitride 10 Round Semi-Auto
Sig Sauer M17X 9mm 4.7in Barrel Coyote 21rd Semi-Auto Pistol
Sig SAUER P322 Compact 22LR Pistol, Fiber Optic Sights, Threaded Barrel
Sig Sauer SCT350 T300 Bullseye Hanging Target Black/White
Sig Sauer SCT357 T300 Multi Zone Hanging Target Black/White
Sig Sauer SCT356 T300 4 Square Hanging Target Black/White
Sig Sauer SCT354 T300 IPSC Hanging Target Black/White Replacement
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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