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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)
Sightmark SM34019 Tactical 30mm Cantilever Scope Mount Matte Black
Sightmark SM13038CR1 Citadel 1-6x24mm Red Illuminated Rifle Scope Black
Sightmark LoPro Mini Green Laser Sight SM25016 - Compact Tactical Accessory
Sightmark LoPro Combo Green Laser & Light 300lm SM25013
Sightmark SM26043-LQD Mini Shot M-Spec Red Dot 1x 3 MOA, 10 Brightness Levels
Sightmark SM39046 .380 ACP Pistol Boresight
Sightmark Ultra Shot M-Spec FMS Reflex Sight
Sightmark Ultra Shot M-Spec LQD Reflex Sight
Sightmark Sm26032 Ultra Shot A-Spec 1X 33X24mm Obj
Sightmark Ultra Shot R-Spec Reflex Sight
Sightmark SM26040 Element Red Dot 1x30mm 2 MOA Picatinny Mount
SightMark LoPro Compact Combo Green Laser Sight
SightMark Ultra Shot R-Spec Reflex Sight - Dark Earth
Sightmark SM26043DE Mini Shot M-Spec 3 MOA Red Dot Sight Dark Earth
Sightmark Mini Shot M-Spec FMS Reflex Sight
Sightmark SM13025001 Wraith HD Quick Detach Mount Matte Black Aluminum
Sightmark SM13080HDR Core HX Black Hardcoat Anodized 3-12x56mm 30mm Tube...
Sightmark SM11034T Latitude 20-60x80 Spotting Scope, Rubber Armor, Waterproof
Sightmark Wolverine FSR Red Dot Sight 1x 28mm Matte Black Picatinny Mount
SIONYX C011500 Aurora Night Vision Monocular with Hard Case
SIONYX C011600 Night Vision Monocular Black Premium
SIONYX K011400 Aurora Pro Explorer Night Vision Monocular
SIONYX Aurora Pro Color Nv Camera
Silver Shadow Gilboa DBR Snake AR15 Rifle - Black 5.56 NATO 16" Double Barrel
Sig Sauer P365 Fuse Semi-automatic Polymer Frame Pistol Compact 9MM 4.3"
Sig Sauer P365 XMacro Striker Fired Semi-automatic Polymer Framed Pistol
Sig Sauer 300 252 0409 11 9mm Optics Ready White Gold
Sig Sauer 300 252 0409 64 9mm Optics Ready Blue Gold
Sig Sauer P365X 300-252-0409-14 9MM 3.1" Gold Barrel 17 Rds Optic Ready
Sig Sauer 300-252-0409-04 P365X 9MM, 3.1" Gold Barrel, 17 Rounds, Black
Sightmark Sm39043 Boresight Red Laser 300 Blackout
Sightmark SM39021 Boresight Laser .22LR Red 2 in Barrel Length
Sightmark SM39031 7mmx65 REM Premium Laser Boresight
Sightmark SM39026 Triple Duty Universal Bore Sight .17 to .50 Caliber
Sightmark SM39024 Boresight .17 to .50 Caliber Aluminum Magnetic In Case
Sightmark SM26047 Mini Shot A-Spec M2 Red Dot Sight 1x23mm Matte Black
Sightmark SM39019 Boresight Red Laser .44 Mag Brass with Battery & Case
Sightmark Sm39018 Boresight Red Laser 38 Special/3
Sightmark SM39017 Laser Boresighter Cartridge 45
Sightmark SM39016 Red Laser Boresight .40 S&W Brass with Battery & Case
Sightmark SM39015 9mm Luger Boresight Red Laser 632-650nM Action Type
Sightmark SM13121MR2 Core TX 2.0 Rifle Scope 4-16x44mm MR2 Illuminated
Sightmark SM39022 Red Laser Boresight 17 HMR Brass with Battery & Case
Sightmark Sm39020 Boresight Red Laser 22-250 Rem/6
Sightmark SM39014 Universal Boresight .17 to .50 Caliber Brass Magnetic
Sightmark SM39012 Laser Boresighter Cartridge 50 Caliber Chamber Brass
Sightmark SM39009 Red Laser Boresight .30-30 Win Brass with Batteries
Sightmark SM17001 Wraith Mini Thermal Rifle Scope 2-16x 35mm Black
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 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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