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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 SOFEC0RS Foxtrot-EDC Flashlight 1350 Lumens Rose Gold/Black
Sig Sauer ROMEO-MSR Gen II 1x20mm Green Dot Sight Black 2 MOA
Sig Sauer SORMSR101 Romeo MSR Gen II 1x20mm 2 MOA Red Dot Matte Black
Sig SAUER Romeo5 Gen ll 1x20mm Compact Green Dot Sight Black (SOR5102)
Sig Sauer SOR5101 Romeo 5 1x20mm 2 MOA Red Dot Matte Black
Sig Sauer CROSS PRS .308 Win 24 in Threaded Barrel Folding Stock 10rd
Sig Sauer Cross STX 308 Win 20 Inch Threaded Precision Rifle Black
Sig Sauer W320F-9-BXR3-PRO-RXX P320 9mm 4.7" Nitron Semi-Auto Pistol
Sig Sauer W320CA-9-BXR3-PRO-RXX P320 Carry Pro 9mm 3.9" Nitron Pistol
Sig Sauer W365XL-9-BXR3P-RXX P365 XL Romeo-X 9mm 3.7" Nitron Pistol
Sig Sauer W365XCA-9-BXR3P-RXX P365 X-Macro 9mm 3.7" Nitron Pistol
Sig Sauer W365X-9-BXR3P-RXX P365X 9mm 3.1" Nitron Semi-Auto Pistol
Sig Sauer SOA63003 Alpha 30mm High Rings Aluminum 6061-T6 Black Set of 2
Sig Sauer SOA63002 Alpha 30mm Medium Rings Aluminum 6061-T6 Black Set
Sig Sauer SOA63001 Alpha 30mm Low Rings Aluminum 6061-T6 Black Set of 2
Sig Sauer SOA64004 Alpha 6 34mm Extra High Scope Ring Set Black Steel
Sig Sauer SOA64003 Alpha 6 34mm High Scope Ring Set Black Stainless Steel
Sig Sauer SOA64002 Alpha 6 34mm Stainless Steel Scope Ring Set Medium
Sig Sauer SOA65004 Alpha 6 Scope Ring Set 35mm Stainless Steel Black
Sig Sauer SOA65002 Alpha 6 35mm Stainless Steel Scope Ring Set Black
Sig Sauer SOZ6B100 Zulu6 Binocular Adapter 42mm Black Nylon
Sig Sauer E29R-9-BSE-R2 P229 Elite 9mm 3.9" DA/SA Night Sights 15-Rd
Sig Sauer E26R-9-BSE-R2 P226 R Elite 9mm 4.4" Black 15-Rd Semi-Auto
Sig Sauer P365XMAC 9MM 21R Coyote Magazine for P365 Series
Sig Sauer P365XMAC 9MM 21R Black Magazine
Sig Sauer W320AXGF-9-LEGION P320 AXG 9mm 3.9" Legion Gray Pistol
Sig SAUER 1911XR-45-CXR3-RXX 1911 X Series 45 ACP 5" Coyote Semi-Auto Pistol
Sig Sauer 1911 X Carry 45 ACP 4.25" Coyote Semi-Auto Pistol 8RD
Sig CROSS6MM24BPRS 6mm Creedmoor 24" 10+1 Gray PRS Bolt Action Rifle
Sig Sauer 8901572 P320 9mm Black Stainless Steel Optic Ready Slide Assembly
Sig Sauer Reserve Collection P320-SXG Handgun 9mm Luger 21rd Magazines(3) 3.9 Compensated Barrel Hi-Polish DLC
Sig Sauer 8901571 P320 Slide 9mm Coyote Brown with ROMEO-X Optic
Sig SAUER P320 9mm 4.7in Romeo-X Pro XRays Black Slide Assembly (8901570)
Sig SAUER P320 Carry/Compact 9mm 3.9in Coyote Brwn Slide Assembly (8901569)
Sig Sauer P320 ROMEO-X 9mm Handgun Slide with Front & Rear Serrations an...
Sig SAUER P320 9mm 3.6in Romeo-X Pro XRays Brown Slide Assembly (8901567)
Slide Assembly W/Romeo-X Pro Sight For Sauer??
Sig SAUER KILO6K HDX 10x42mm Sage Green Rangefinder Binocular (SOK6K106)
Sig Sauer 8901559 P365XL 9mm Coyote Cerakote Stainless Steel Slide
Sig Sauer 8901558 P365xl 9MM Luger Black Cerakote Stainless Steel Serrated
SIG SAUER P320 M18 Carry 9mm Coyote PVD Semi-Auto Pistol
SIG 320XF9BXR3RXX10 P320 9mm 4.7" 10+1 Black Optic Ready XFull
SIG 320XC9BXR3RXX10 P320 9mm 3.6" 10+1 Black Optic Ready XCompact
Sig P320AXGF9LEGIONRXX10 9mm 3.9" 10+1 Legion Gray Optic Ready
P365 AXG LEGION Pistol: Alloy Macro Grip, G10 Panels, Optics Cut, XRAY Sights
Sig Sauer WE26R-9-BSE-RX-SAO P226 Elite 9mm 4.4" Nitron Semi-Auto Pistol
Sig Sauer WE26R9BSERX P226 Elite 9mm 4.4" Nitron Semi-Auto Pistol
Sig Sauer W320CA-40-BXR3-PRO P320 Carry Pro 40 S&W 3.9" Nitron 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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