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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 SOSBDX46111 50MM Digital Ballistic Scope Black
Sig Sauer SOSBDX44111 44MM Digital Ballistic Scope Black
Sig Sauer 322C-BAS-CA P322 22LR 4" Black Anodized Pistol, Fiber Optic Sights
Sig Sauer SLH 7.62 Clutch-Lok QD Suppressor
Sig Sauer NG762QD SLH 7.62mm 1.67" Black Inconel Suppressor
Sig Sauer SLX 5.56 inconel QD Suppressor
Sig Sauer NG556-QD 5.56 Suppressor SLXC 1/2x28 Black
Sig SAUER P365 XMacro Comp 9mm 3.1in 2x10rd Semi-Auto Pistol CA Compliant
Sig Sauer SOR5193 Romeo5 Gen II 1x20mm Red Dot Sight Black IPX-7 Waterproof
Sig Sauer MCX Rattler LT Semi-Automatic Tactical Pistol 223 Remington
Sig Sauer SORX1231 Romeo X Reflex Pistol Sight 3 MOA Red Dot
SIG SAUER RMCX-762R-16B-IR 7.62x39mm 16" FDE Rifle 28+1 Semi-Auto
Sig SAUER MCX 5.56 NATO 16in 30rd IR Cerakote FDE Rifle RMCX-556N-16B-IR
Sig SAUER MCX Spear-LT IR 5.56 NATO 11.5in 10rd FDE Semi-Auto Pistol
Sig Sauer MCX SPEAR 5.56 NATO 30+1 FDE Cerakote 11.5" Pistol Cane Brace
Sig Sauer SOF12002 Foxtrot1X 450 Lumens Light Flat Dark Earth IPX7
Sig Sauer CROSS 6.5 Creedmoor Rifle 5+1, Carbon Fiber Barrel, Moss Green
ROMEO5 Gen II & Juliet3 Micro Magnifier Combo: 1x Red Dot Sight, IPX-7 Waterproof
ROMEO-X Enclosed Reflex Sight Advanced Optics
ROMEO-X Enclosed Reflex Sight: High Precision Optics
ROMEO-X Enclosed Reflex Sight: High Precision Optics for Sharp Shooting
ROMEO-X Enclosed Reflex Sight: High Precision Optics
Sig Sauer P320 X5 Legion Semi-Automatic Pistol 9mm Luger
Sig Sauer 1911XC RX 45AP 8+1 X-Ray3 Sights Romeo-X Red Dot 4.25" Black
Sig Sauer P320XF 9MM 10+1 X-Ray3 NS MS CA Compliant Pistol
Sig Sauer WM18-9-PRO-BLK-MS-RM17 M18 9mm 3.9" Black Semi-Auto Pistol
Sig Sauer WM17-9-PRO-MS-RM17 P320 M17 9mm 4.7" Coyote Semi-Auto Pistol
Sig Sauer WM17-9-PRO-BLK-MS-RM17 P320 M17 9mm 4.7" Black Pistol
Sig Sauer Romeo MSR Gen II 1x20mm 2 MOA Red Dot Matte Black Combo
Sig Sauer P320 9mm Luger 4.7" Barrel
Sig SAUER P320 9mm 3.9In Blk Striker Siglite (2) 10Rd Pistol 320C-9-BSSP-10
Sig Sauer W320C-9-BXR3-PRO-RXX P320 Pro 9mm 3.6" Nitron Pistol
Sig SAUER M400-SDI X 5.56 NATO 11.5in Semi-Auto Pistol (PM400-SDI-11B-BLK)
Sig SAUER M400 Thread 5.56mm NATO 11.5in 30rd Pistol PM400-11B-TRD-V2
Sig Sauer W320CA-9-BSSP-MS P320 Carry 9mm 3.9" Nitron Semi-Auto Pistol
Sig Sauer W320C-9-BSSP-MS P320 Compact 9mm 3.9" Nitron Semi-Auto Pistol
P365 Fuse 9mm Luger Semi-Auto Handgun - Romeo X Compact Included
Sig Sauer P365 Fuse 9mm 4.3in 10rd Optic Ready Black Nitron Pistol
Sig Sauer P365 Fuse 9mm 21+1 Fiber Optic Black Slide Serrations
SIG 8901673 MCX MPX PCB Brace Coyote Fixed Folding Hinge 1913 Interface
Sig SAUER MPX/MCX Fixed/Folding with Locking Hinge Pistol Brace (8901672)
Sig Sauer P365 Semi-Automatic Pistol 9mm Luger 3.1" Barrel
Sig Sauer W320F-9-BSSP-MS P320 9mm 4.7" Nitron Semi-Auto Pistol
Sig Sauer W320F-9-BSSP P320 9mm 4.7" Nitron Semi-Auto Pistol
Sig Sauer W320CA-9-BSSP P320 Carry 9mm 3.9" Nitron Semi-Auto Pistol
Sig Sauer W320C-9-BSSP P320 Compact 9mm 3.9" Nitron Semi-Auto Pistol
Sig Sauer 229R-9-BSE-R2 P229 R Elite 9mm 3.9" Black Semi-Auto
Sig SAUER P226 Elite 9mm 4.4in 2x10rd Black DA/SA Pistol (226R-9-BSE-R2)
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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