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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 P229 Compact M11-A1 Pistol 9mm
Sig Sauer P226 MK25 Pistol 9mm 15 Round With Night Sights
Sig Sauer P226 Scorpion 9mm Luger 4.40" 10+1 Flat Dark Earth Hogue Extreme G10
Sig Sauer P226 9mm Full Size Extreme Handgun
Sig Sauer M11-A1 9mm 3.9" 15rd M11A1
Sig Sauer P938 Micro-Compact 9mm SAO Pistol Nitron BLK
Sig Sauer Flip-Up Iron Sight Set for M1913 Rail Mount - SITE-SET-1913-FLIP
SigTac SP2022 9mm Magazine 17 Rounds Md: MAG-2022-9-17
Sig Sauer WMK25 P226 MK25 9mm 4.4" Black Semi-Auto Pistol
Sig SAUER P938 9mm 7-round Pistol Magazine (MAG-938-9-7)
Sig Sauer Magazine P938 9MM Luger 6-ROUNDS Black
Sig Sauer MK25-10 P226 9mm 4.4in Barrel Black 10rd Semi-Auto
Sig Sauer P226 MK25 9mm 4.4" SIGLITE Night Sights 10rd Black
SIG Sauer P220 Full-Size Semi-Auto Handgun in 45 ACP and 10mm
Sig Sauer 1911 .45 ACP 5.00" 8-Rounds
Sig Sauer 1911R45BSSCA Full-Size 45 ACP 5" 8+1 Black Nitron Stainless Steel Frame & Slide Rosewood
Sig Sauer BBL22919 P229 9mm Luger 3.90" Black Nitride Barrel
Sig Sauer P229 Enhanced Elite Compact 9mm Pistol
Sig Sauer Magazine P238 380 ACP 7Rd W/X-Grip Extended MAG2383807X
Sig Sauer Magazine P229 9mm 15Rd E2 & UPDATED Models MAG229915E2
Sig Sauer Magazine P228/P229 9mm 10 Rounds MAG229910
Sig Sauer Mag 380 ACP 6Rd Blue P238 Mag-238-380-6
Sig Sauer P229 9mm Luger 3.90" Nitride Finish Steel Barrel for P228
Sig Sauer Magazine 1911 Compact 45 ACP 7 Rounds Md: MAG1911457
Sig Sauer Mag 45 ACP 10 Rounds Stainless P220 Mag-220-45-10
Sig Sauer Magazine 1911 45 ACP Fullsize Carry 8Rd MAG1911458
Sig Sauer Mag 357 40 S&W 10 Rounds Blue P229 Mag-229-43-10
Sig Sauer P226 Magazine .40 S&W/.357 SIG 15rd Steel Blued
Sig SAUER Mags 9MM 20Rd Blue P226 MAG-226-9-20
Sig Sauer P226 9mm Threaded Barrel M13.5x1 LH Black
Sig Sauer P226 Magazine 9mm 15rd Steel Blued
Sig Sauer Mag 9MM 10 Rounds Blue P226 Mag-226-9-10
Sig Sauer SP2022 Magazine .357 .40 S&W Black 1
Sig Sauer 12 Round Blue Magazine For P229 40 S&W/ 357 Md: K00002
Sig Sauer Handgun Magazine For SP2022 9mm Luger 1
Sig Sauer 1600022 Locking Insert Blue Two Tone SP2009
Sig Sauer Magazine P226 357Sig 40 S&W 12Rd MAG2264312
Sig Sauer BBL22640 P226 .40 S&W 4.4" Black Nitride Barrel
Sig Sauer P232 Trigger SS Two Tone Silver 34232312
Sig Sauer LEVER-15 Safety Lever Blued Two-Tone for P226
Sig Sauer P229 Barrel 357 SIG 3.9" Blued
Sig Sauer BBL22940 P229 3.9" .40 S&W Black Nitride Steel Barrel
Sig Sauer 10 Round Blue Magazine For Model 2022 Caliber 9MM MAG2022910
Sig Sauer Mag 45 ACP 8Rd Stainless P220 Mag-220-45-8
Sig Sauer SP2022 Magazine 40/357 10RD Steel Black
Sig Sauer MAG229913 9mm 13-Round Steel Pistol Magazine Blued Finish
Sig Sauer MAG23998 P239 9mm 8-Round Steel Blued Magazine
Sig Sauer P226 Magazine 10rd 40 S&W/357 SIG Stainless Steel Blued
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.
SilencerCo Sparrow 22 Rimfire Suppressor 22LR 5.08" Stainles
SIG SAUER 322C-ROSE-RS P322 Rose 22 LR 4" Black Anodize Semi
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
Sig Sauer W365XL-9-BXR3P-MS P365 XL 9mm 3.7" Nitron Semi-Aut
Sig Sauer 2401191R Picatinny Stock Adapter for AR-15, Alumin
Sig Sauer SORX1080 24MM Black Pro Optics Ready Sight
SIG SAUER E26R-9-BSS-FBZ P226 Full-Size 9mm 4.4" 2-Tone Bron
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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