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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 8900791 P320 9mm 4.7" Gold Nitride Barrel for Full-Size Models
Sig Sauer P320 Compact 8900790 - 9mm Luger, 3.90" Barrel, Gold Titanium-Nitride Finish
Sig Sauer 8900789 P320 Subcompact 9mm Luger 3.7" Gold Barrel Non-Threaded
Sig SAUER Juliet5-Micro 5x24mm Black Magnifier (SOJ5M001)
Sig SAUER P365 Custom Works Fire Control Unit 9/380 Flat Blade Gold Frame
Sig Sauer P365XL 8900777 9mm Luger 3.7" Gold Barrel w/LCI Non-Threaded
Sig Sauer P365 9mm Luger 3.10" Gold Titanium Nitride Loaded Chamber Indi...
Sig Sauer 8900763 LXG Grip Module Laser Engraved 9mm Luger P365XL Black
Sig Sauer 8900758 P322 Ambidextrous IWB-OWB Black Composite Belt Clip F...
Sig Sauer P365XL Barrel 9mm Luger 3.7 in Black Nitron Action Type
Sig SAUER P322 22 LR 25rd Polymer Black Magazine (8900746)
Sig SAUER P322 22 LR 20rd Polymer Black Magazine (8900745)
Sig Sauer P320-XTEN 10mm Auto 15-Round Factory Magazine
Sig Sauer Clutch-Lok QD Muzzle Brake Stainless Steel 5-8" 24 TPI for 7.62mm
Sig Sauer SL76258X2425DEGM Clutch-Lok QD Muzzle Brake 7.62mm Black
Sig Sauer Clutch-Lok QD Muzzle Brake 5.56mm 90 Degree Taper
Sig Sauer Clutch-Lok QD Muzzle Brake 5.56mm 25 Degree Taper
Sig Sauer Clutch-Lok QD Flash Hider Stainless Steel 5-8" 24 tpi Threads ...
Sig Sauer SL-762-58X24-25DEG-F Flash Hider 7.62MM 25 Degree Taper
Sig SAUER Clutch-Lok QD 5.56mm 90-Degree Shoulder Flash Hider
Sig Sauer Clutch-Lok QD Flash Hider 5.56mm Black Stainless Steel 2.10" OAL
Sig Sauer Tango-MSR LPVO 1-8x24mm Red Illuminated BDC8 Reticle
Sig Sauer SOTM61001 Tango MSR 1-6x24 30MM Hellfire Reticle Scope
Sig SAUER Tango MSR Scope 1-10X28mm 34mm SFP Illum BDC10 Reticle SOTM11000
SIG Sauer Alpha Cantilever Mount 34mm Tube Steel Alloy
Sig SAUER Alpha Cantilever Mount 30mm Tube Black Steel Alloy
Sig Sauer RomeoZero Mounting Kit for Hellcat/Glock 43x
Sig Sauer SOR0SK001 RomeoZero Shroud Kit Black for P365X/XL Handgun
Sig SAUER .380 Auto For P365 Microcompact 12rd Black Magazine (8900716)
Sig SAUER .380 Auto f/P365 Microcompact 10rd Finger Extension Blk Magazine
Sig Sauer P365 Flush Magazine .380 ACP 10-Round Black
Sig Sauer WRM400-556N-16B-PRO M400 Pro 223/5.56 16" Black Rifle
Sig Sauer WRM400-556N-14B-PRO-SBR M400 SBR 223/5.56 14.5" Black Rifle
Sig Sauer WRM400-556N-11B-PRO-SBR M400 SBR 223/5.56 11.5" Black Rifle
Sig Sauer 8900696 Tread M400 Two-Stage Trigger Kit 5 lb Pull
Sig Sauer P320 X-Carry Legion Double Action Only Semi-Automatic Pistol 9mm
Sig Sauer Airsoft P365 Magazine Black 6mm BB 12/Rd
Sig Sauer P365XL Recoil Spring Assembly 9mm Compatible with P365-XMACRO
Sig Sauer 8900674 TXG Grip Module P320 X-Carry 9/40/357 Gray
Sig Sauer BuckMaster 3-12x44 Rifle Scope Hellfire BDC Reticle Waterproof
Sig Sauer Juliet3-Micro Magnifier 3x22mm FDE
Sig P320 XTEN 10mm Auto Pistol Black 5" Optic Ready
Sig Sauer AIRP320XCABB CO2 Air Pistol 4.5" Barrel 350 fps 21rd Magazine
Sig Air-1911es-bb .177bb Emperor Scorpion Co2
Sig Sauer Buckmasters 3-12x44mm Rifle Scope 1" Tube BDC Reticle
Sig SAUER Buckmasters 3-9x50mm 1in SFP BDC Reticle Riflescope SOBM33002
Sig SAUER Buckmasters Rifle Scope 3-9x40mm BDC Reticle Black
Sig Sauer W320AXGF-9-BXR3-R2 P320 AXG 9mm 4.7" Nitron Semi-Auto 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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