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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 (2,382)
Sierra MatchKing 7mm 175gr HPBT Match Grade 500 Box
Sierra Tipped GameKing 30 Win Mag 180Gr Premium Bullets
SIG SAUER SIG M400
SIG SAUER SIG M400
SIG SAUER SIG M400
SIG SAUER 1304117-R
Black Powder-Free Nitrile Gloves
Pistol & Rifle Sights - 1203637F-06-R
P226, Full Size
P226, Full Size
SIG Sauer P226 XCarry 9mm 3.8 In Optic-Ready w/ Romeo X & X-RAY3 Sights
P226, Full Size
SIG SAUER P226 9mm 4.4 In
P226, Full Size
P226, Full Size
SIG SAUER SIG LOC 320 First Responder Purchase Only
SIG SAUER LOC 320 First Responder Purchase Only
SIG Loc 320
SIG Loc 320
SIG Loc 320
SIG SAUER SIG LOC 320 First Responder-Only Lock
SIG Loc 365
MCX-SPEAR LT 5.56 16"" RIFLE
P365-XMacro Magazine Funnel
SIG P365 XL LE 9mm 3.7in 12+1 ROMEOZero Elite Optic
Barrels & Accessories - 1303065-03-R
P320 Pro Carry LE
RIFLE SUPPRESSOR
Pistol & Rifle Sights - 1203629F-08-R
P320 AXG Magazine Funnel
P320 Walnut AXG Grip Set
SIG SAUER SLH QD .300 BLK Clutch-LOK, Subsonic/Supersonic Optimized
P320 Rear Sight Assembly
P365X Rear Sight Assembly
Trigger, Flat, 320 90 Deg Break, Black Oxide
P320 9mm Extended Magazine
M17 Extended Magazine
P250/P320 Magazine
P320X Magazine Funnel
P320X Grip Weight
Sight, Flip-Up, Rear, Gen 2
Sight, Flip-Up, Front, Gen 2, Tall Post
Magazine, 9, FULL, 17 RD, SNAP RET., MG, BLK
Pkit, P320, 9/40/357, Compact/Carry
P250/P320 Subcompact Magazine
SIG SAUER SIG716G2 DMR 7.62x51mm 18 In 2-Stage Match Trigger
Sear Spring
Sinterfire SF300BLK110RHA 300 BO Rha 110G LF 50
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 E26R-9-BSS-FBZ P226 Full-Size 9mm 4.4" 2-Tone Bron
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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