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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 W320AXGCA9BXR3R2 P320 AXG 9mm 3.9" Nitron Semi-Auto Pistol
Sig SAUER 277 Fury Hybrid AccuBond 150Gr 20rd Rifle Ammo H277SFAB150-20
Sig Sauer 8900567 P320 9mm Threaded Barrel 4.6" Black Nitron Finish
Sig Sauer 8900566 P320 9mm 5.5" Threaded Barrel Black Nitron Finish
Sig Sauer P320 30rd 9mm Luger Extended Magazine Coyote Brown
Sig Sauer P320 9mm 30-Round Extended Magazine
Sig Sauer WRMCX-762R-16B-LT MCX Spear-LT 7.62x39mm 16" Nitride Rifle
Sig Sauer WRMCX-762R-11B-LT-SBR MCX Spear-LT 7.62x39mm 11.5" Nitride SBR
Sig Sauer WRMCX-556N-9B-LT-SBR MCX SBR 223 Rem | 5.56 NATO 9" Black Rifle
Sig Sauer WRMCX-556N-16B-LT MCX Spear-LT 223/5.56 16" Black Rifle
Sig Sauer WRMCX-556N-11B-LT-SBR MCX SBR 223 Rem | 5.56 NATO 11.5" Black
Sig Romeo 2 Red Dot Sight 6 MOA Black
SIG SAUER ROMEO2 Reflex Red Dot Sights Black 3 MOA
Sig SAUER P320 XCarry Legion 9mm 4.6in Brl 3x 17rd Mags Gray Pistol
Sig Sauer Elite Defense 10mm Auto 200 gr V-Crown JHP
Sig SAUER Buckmasters 1500 Black Laser Rangefinder (SOK15601)
Sig Sauer KILO4K 6x22mm Laser Rangefinder
Sig Sauer Electro-Optics SOF12001 Foxtrot1X Tactic
Sig Sauer Elite Hunting 6.5 Creedmoor 140 gr 2650 fps Nosler AccuBond
Sig SAUER Elite Hunting .308 Win 165Gr AccuBond Ammo 20 Rounds
Sig Sauer E270AB150-20 .270 Winchester 150 gr AccuBond 20 Rounds
Sig Sauer 8900448 Ambidextrous Charging Handle
Sig Sauer 716I Tread 3-Chamber Muzzle Brake
Sig Sauer P320 9mm 4.3" Black Threaded Barrel
SIG Sauer P320/250 Compact 9mm Threaded Barrel 4.6" Black
Sig Sauer P320 9mm Threaded Barrel 5.5" Black Nitron
SIGA SLH300TI 300 Blackout 1.67" D 8.80" L Black Titanium DT Mount
Sig Sauer SLH762QD 7.62mm 1.67" D 7.49" L Black Inconel QD
Sig Sauer SLH762TICQD Compact 7.62mm Titanium Suppressor
Slh762ti-qd Suppressor 7.62mm Titanium Core Qd Mou
Sig Sauer Tango MSR LPVO Rifle Scope 1-6x24mm 30mm Tube Illuminated BDC6 Reticle
Sig SAUER P320MAX 9mm Striker-Fired Pistol, Carry Optics, TXG Grip, ROMEO3MAX, 5" Barrel, 4 Steel Mags
Sig SAUER Cross 6.5 Creedmoor 24in Caliber X-Change Kit (8900426)
Sig Sauer P365/365XL IWB/OWB Holster Ambidextrous Black
Sig Sauer KILO6K HD 10x32mm Binocular Rangefinder OD Green
Sig Sauer TANGO6T 1-6x24mm Rifle Scope FL-6 Hellfire Reticle
Sig Sauer P322 22LR Pistol 4" Barrel Fiber Optic Sights Black
SIG Sauer P322 22 LR 4 in Black Threaded Barrel 20 Round Semi-Automatic
Sig P365-380 Micro-Compact .380 ACP Pistol with Safety
Sig Sauer P365-380 Micro-Compact .380 ACP Pistol
Sig Sauer P226X5 Legion 9mm 10+1 XRAY3 Suppressor Height Sights
"Sig Sauer P226 XFIVE Legion 9mm Single-Action Alloy Frame with 4.4" Barrel, Adjustable Trigger, Xray3 Sights, Legion Gray Cerakote, 20 Round Magazines
Sig Sauer SOR2M100 Universal Reflex Sight Riser Mount, Black Finish
Sig Sauer 8900373 P320 9MM 10RD Magazine Coyote Floor Plate
SIG Sauer Juliet 3-Micro Magnifier Black 3x22mm
Sig Sauer 1303084-R RMR/SRO Sealing Plate Kit for P320
SIG Sauer 365XL Grip Module Assembly - 9mm Manual Safety, Black
SIG Sauer 365XL Grip Module Assembly - 9mm Standard Coyote
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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