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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 (2,380)
SilencerCo Velos LBP 5.56 NATO/.223 4.76 In Low Back-Pressure Black
Sig Sauer P320 FLUX 9MM 3.9" 30RD Legion 320
Sig SAUER MCX-SPEAR 6.8x51mm SBR 13in Semi-Auto Rifle RSPEAR-68-13B-NG-SBR
Sig Sauer P365X Macro Tacops 9mm 3.7" 17rd Pistol
SIG SAUER MCX Spear SBR 7.62x51mm 13" Nitride NFA
SIG SAUER ZIP UP HOODIE, VINTAGE SS LOGO, GUNMETAL, XXL
SIG SAUER ZIP UP HOODIE, VINTAGE SS LOGO, GUNMETAL, XL
SIG SAUER ZIP UP HOODIE, VINTAGE SS LOGO, GUNMETAL, LARGE
SIG SAUER T-SHIRT, SWISS SAUER LOGO, WHITE, MEDIUM
SIG SAUER HAT, MAX MICHEL SIGNATURE, SIG MARK, FLEX FIT DELTA, BLACK
SIG SAUER T-Shirt 5.11 Schematic Flag Flint XL
SIG SAUER T-Shirt 5.11 Schematic Flag Flint Medium
SIG SAUER T-Shirt 5.11 Schematic Flag Flint Large
SIG SAUER T-Shirt 5.11 Schematic Flag Flint XXL
SIG SAUER 5.11 CHROME EAGLE EMBLEM SS TEE, HEATHER GRAY, 2XL
SIG SAUER 5.11 CHROME EAGLE EMBLEM SS TEE, HEATHER GRAY, XL
SIG SAUER 5.11 CHROME EAGLE EMBLEM SS TEE, HEATHER GRAY, LARGE
SIG SAUER 5.11 CHROME EAGLE EMBLEM SS TEE, HEATHER GRAY, MEDIUM
SIG SAUER T-SHIRT, SWISS SAUER LOGO, WHITE, XXL
SIG SAUER T-SHIRT, SWISS SAUER LOGO, WHITE, XL
SIG SAUER T-SHIRT, SWISS SAUER LOGO, WHITE, LARGE
SIERRA BULLETS 6MM .243 116GR TIPPED MATCHKING
SIG SAUER SOK3K601 Kilo4K Rangefinder Graphite BDX 2.0 Enabled 5 Target & 5 Range Modes CR2 Battery SOK3K601 | RANGEFINDER
SIG SAUER 320XF-9-BXR3-RXSL P320 X-Full 9mm 4.7" Nitron Semi-Auto Pistol
SIG SAUER 320XC-9-BXR3-RXSL P320 X-Compact 9mm 3.6" Nitron Semi-Auto Pistol
SIG SAUER P320V006-RXP P320 Spectre 9mm 4.6" Coyote Cerakote Semi-Auto Pistol
Sig Sauer P211 GTO RXSL Semi-automatic Single Action Only Metal Frame
Sig Sauer P365 AXG LUXE Semi-automatic Striker Fired Metal Frame Pistol
Sig Sauer Rear Sight Fits P211 Matte Black Finish
Sig Sauer M18 Semi-automatic Striker Fired Polymer Frame Pistol Carry Size
Sig Sauer MCX-Spear LT Complete Upper Receiver 300 Blackout 9" Threaded
Sig Sauer P320 AXG Legion Semi-automatic Striker Fired Metal Frame Pistol
Sig Sauer MCX-Rattler LT Complete Upper Receiver 300 Blackout 6.75"
Sig Sauer P365 Fuse Duck Camo 2 Handgun 9mm Luger 21(2)&17(1)rd Magazines 4.3 Barrel LXG Front Optic Sight
Sig Sauer P365 Fuse Two-Tone Tan Handgun 9mm Luger 21(2)&17(1)rd Magazines 4.3 Barrel LXG Front Optic Sight
Sierra Bullets Sig Sauer V-Crown 9mm .355 124 Gr JHP 500 Rounds
sig sauer 8901966
sig sauer 8901961
SIG SAUER E26R-9-BSS-FBZ P226 Full-Size 9mm 4.4" 2-Tone Bronze Semi-Auto Pistol
Sig Sauer Zulu4 HD 12x50 Marine Binoculars Orange
SIG SOZ40001OR ZULU4 HD 10X42 MARINE BINO ORANGE
Sig Sauer P365 X Macro 9mm 17Rd Optics Ready
SIG SAUER 226X5-9-CL2-SAO-10 P226 X-Five CL2 9mm 5" Stainless Semi-Auto Pistol
SIG SAUER 226X5-9-CL2-SAO P226 X-Five CL2 9mm 5" Stainless Semi-Auto Pistol
Sierra MatchKing 7mm 175gr HPBT Match Grade 500 Box
Sierra Tipped GameKing 30 Win Mag 180Gr Premium Bullets
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 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 P365 9mm 3.1 Inch NITRON Striker Fired Compact Han
Sig Sauer P226 X-Five Extreme Semi-automatic Single Action O
Sig Sauer P226 Magazine 10rd 40 S&W/357 SIG Stainless Steel
Sig Sauer P365X Semi-automatic Striker Fired Polymer Frame P
Sig Sauer SOTMC11002 TANGO 1-10x24 FFP Scope, 30mm Tube, BDC
Shop SI Products
Sig SAUER MCX-SPEAR 6.8x51mm SBR 13in Semi-Auto Rifle RSPEAR
Sig Sauer P320 FLUX 9MM 3.9" 30RD Legion 320
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
Sierra 1502 BlitzKing Rifle Bullets 6mm .243 55gr 100ct
Sierra MatchKing-X Rifle Bullets .30 Cal 175 gr HPBT 500/ct
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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