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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 Cross Magnum Rifle .300 Win Mag 6rd Magazine 24" 5-8x24 Thread...
Sig SAUER Romeo-X Compact Sight 2MOA Circle Dot Flat Dark Earth RMSc Mount
Sig Sauer P320 10mm 5" 10+1 Black Optic Ready Pistol
Sig Sauer W365XCA-9-COMP P365 X-Macro 9mm 3.1" Nitron Semi-Auto Pistol
Sig Sauer W365XCA-9-COMP-RXX P365 X-Macro Comp 9mm 3.1" Nitron Pistol
Sig Sauer Magazine P320 10MM Black 10Rd 8901659
Sig Sauer 220R-45-BSE-R2 P220 R Elite .45 ACP 4.4" Barrel Black OR
Sig Sauer SOW46002 Whiskey4 6-24x50mm 30mm Tube Illuminated Reticle
Sig Sauer SOW46001 Whiskey4 6-24x50mm MOA Milling Hunter Riflescope
Sig Sauer W320F-40-BXR3-PRO P320 Full 40 S&W 4.7" Nitron Semi-Auto Pistol
Sig Sauer P320 320F-9-BSSP 9mm 17+1 Optics Ready Nitron Finish Black
P320 Compact 9mm Luger Semi-Auto Handgun - High Precision Shooting
Sig Sauer Cross-Magnum Bolt Action Rifle 300 Winchester Magnum 24"
Sig Sauer SOZC0002 Canyon HD 12x50 Binoculars, HD Glass, IPX-7 Rated
Sig Sauer KILO10K-ABS HD Gen II Rangefinder Binocular: Enhanced Optics & Wind Input
Sig Sauer SOZ80003 Zulu8 HDX 12x50mm Binoculars, Dark Earth, Rubber Armor
Sig Sauer SOZ80002 Zulu8 HDX 10x50mm Binoculars, Dark Earth, Rubber Armor
Sig Sauer SOR5105 Romeo5 Gen II 1x20mm Red Dot Sight Black IPX-7 Waterproof
Sig Sauer WHISKEY4 2.5-10x42 - 30mm Tube, Hellfire Quadplex, Black SOW42004
Sig Sauer WHISKEY4 2.5-10x42 Quadplex Reticle, 30mm Tube - Black SOW42003
Sig Sauer SORX1280 24MM Black Compact Optics Ready
Sig SAUER Romeo-X Compact Black 6 MOA Red Dot Reflex Sight (SORX1260)
Sig Sauer SORX1208 Romeo-X 1x24mm Red Dot Sight Black/Rose Gold
Sig Sauer SORX1080 24MM Black Pro Optics Ready Sight
Sig SAUER Romeo-X Pro Black 6 MOA Red Dot Reflex Sight (SORX1060)
Sig Sauer Romeo-X Pro 1 x 24 mm 2 MOA Red Dot 32 Circle Flat Dark Earth
Sig SAUER P365 XMacro Compact 2A 9mm Luger 3in 3x17rd Coyote Tan Pistol
Sig Sauer TANGO MSR 5-30x56 FFP MRAD Scope - 34mm Tube, Illuminated Reticle
Sig Sauer Tango MSR 5-30X56 34MM Illuminated 0.25 MOA Black Scope
Sig Sauer SOTM63001 TANGO-MSR 3-18x50 FFP Rifle Scope, MRAD Reticle, Black
Sig Sauer SOTM63000 TANGO-MSR 3-18x50 FFP Scope, 34mm, Illum. Reticle
SIG Sauer SOTM62001 TANGO-MSR 2-12x44 FFP Rifle Scope, 34mm, MRAD, Black
Sig Sauer Tango MSR 2-12X44 FFP Illuminated 34MM Black Scope
Sig Sauer P365 X-Macro Grip Module Alloy Matte Finish
Sig Sauer 365AXGF9BFO P365 Fuse Compact Frame 9mm Luger 17+1 4.30" Black...
Sig P320 10MM X-SERIES 5 OPTIC READY 15RD COY
Sig Sauer 1911X RX 45AP 8+1 X-Ray3 Sights Romeo-X Red Dot Black DLC
Sig SAUER P365 2A 9mm 3.1" XRay3 Sights 2x10rd/1x12rd Pistol 365-9-CXR3P-2A
Sig Sauer SOZ10002 Zulu10 HDX 10x50mm Binoculars, Coyote, Waterproof
SIG SAUER P320-XFIVE SXG 9mm 5in 3 21rd Mag Semi-Auto Pistol 320SXG5-9-STAS
Sig SAUER 1911XR-45-SS 45 ACP 5" Stainless Semi-Auto Pistol 8+1 Capacity
Sig Sauer MCX Spear 762NATO 16" Barrel Multicam Cerakote M-LOK Ambi Controls
Sig Sauer WM18-9-PRO-RM17 M18 9mm 3.9" Coyote Semi-Auto Pistol
Sig Sauer WM18-9-PRO-BLK-RM17 M18 9mm 3.9" Black Semi-Auto Pistol
Sig Sauer M17X 9mm 4.7in Coyote 21rd
Sig Sauer P320-M17 9mm 4.7in 3x10rd Coyote Tan
Sig Sauer W1911XR-45-BXR3 1911 X Series .45 ACP 5" Black DLC Pistol
Sig Sauer W1911XCA-45-BXR3 1911 X Carry 45 ACP 4.25" Black DLC Pistol
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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Choose SI for straightforward, well-engineered accessories that improve usability and durability without unnecessary complexity....
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