Buy SI Online

"Innovative firearm accessories engineered for performance"

SI designs rugged, user-focused firearm components and optics. They make accessories like slide plates, charging handles, barrel clamps, red dots, and shotgun parts.

5.0★★★★★(82 verified SI reviews)
Shop All SI Products
7,545
Products
2,384
In Stock
-
Founded
USA
Origin

All SI Products (2,384)

Buy Sig Sauer P365X Semi-automatic Striker Fired Polymer Frame Pistol Compact online Sig Sauer P365X Semi-automatic Striker Fired Polymer Frame Pistol Compact Buy Sig Sauer P365X Semi-automatic Striker Fired Polymer Frame Pistol Compact online Sig Sauer P365X Semi-automatic Striker Fired Polymer Frame Pistol Compact Buy Sig Sauer AIRP320SC177BLK 177 Optics Ready Black Tactical online Sig Sauer AIRP320SC177BLK 177 Optics Ready Black Tactical Buy Sig Sauer P365X Semi-automatic Striker Fired Polymer Frame Pistol Compact online Sig Sauer P365X Semi-automatic Striker Fired Polymer Frame Pistol Compact Buy Sig Sauer SOA55005 35mm 1.535 Alpha5 Scope Mount online Sig Sauer SOA55005 35mm 1.535 Alpha5 Scope Mount Buy Sig Sauer SOA55004 35mm Alpha5 Scope Mount Tactical online Sig Sauer SOA55004 35mm Alpha5 Scope Mount Tactical Buy Sig Sauer SOA54005 34mm Optics Ready Scope Mount online Sig Sauer SOA54005 34mm Optics Ready Scope Mount Buy Sig Sauer SOA54004 34mm Alpha5 Scope Mount Tactical online Sig Sauer SOA54004 34mm Alpha5 Scope Mount Tactical Buy Sig Sauer P365 Fuse 9mm 4.3in Optic Ready 21RD Semi-Auto Pistol online Sig Sauer P365 Fuse 9mm 4.3in Optic Ready 21RD Semi-Auto Pistol Buy Sig Sauer MH68MM113B920 Hybrid 6.8mm 113gr 920rnds *Crate online Sig Sauer MH68MM113B920 Hybrid 6.8mm 113gr 920rnds *Crate Buy Sig Sauer 4204140R MCXSPEAR Long Stroke Piston Tactical online Sig Sauer 4204140R MCXSPEAR Long Stroke Piston Tactical Buy Sig Sauer P365X Full Size Rose Gold Handgun 9mm Luger 12rd Magazines (2) 3.1 Barrel Black online Sig Sauer P365X Full Size Rose Gold Handgun 9mm Luger 12rd Magazines (2) 3.1 Barrel Black Buy Sig Sauer P365 XMacro Handgun 9mm Luger 17rd Magazines (2) 3.7 Barrel Two Tone Green TB online Sig Sauer P365 XMacro Handgun 9mm Luger 17rd Magazines (2) 3.7 Barrel Two Tone Green TB Buy Sig Sauer P365 XMacro Handgun 9mm Luger 17rd Magazines (2) 3.7 Barrel Two Tone Green TB with Optic online Sig Sauer P365 XMacro Handgun 9mm Luger 17rd Magazines (2) 3.7 Barrel Two Tone Green TB with Optic Buy Sig Sauer P365 XMacro Handgun 9mm Luger 17rd Magazines (2) 3.7 Barrel Two Tone Tan TB online Sig Sauer P365 XMacro Handgun 9mm Luger 17rd Magazines (2) 3.7 Barrel Two Tone Tan TB Buy Sig Sauer P365X 9mm 12Rd Night Sights Optics Ready online Sig Sauer P365X 9mm 12Rd Night Sights Optics Ready Buy Sig Sauer M18 9mm 21Rd Night Sights Coyote Pistol online Sig Sauer M18 9mm 21Rd Night Sights Coyote Pistol Buy Sig Sauer M17 9mm 21Rd Night Sights Coyote 4.7in online Sig Sauer M17 9mm 21Rd Night Sights Coyote 4.7in Buy Sig Sauer P320 9mm 17Rd Night Sights Optics Ready online Sig Sauer P320 9mm 17Rd Night Sights Optics Ready Buy Sig Sauer W320C 9mm 15Rd Night Sights Optics Ready online Sig Sauer W320C 9mm 15Rd Night Sights Optics Ready Buy SIMUNITION 8971835 Womens Lightweight Protective Vest online SIMUNITION 8971835 Womens Lightweight Protective Vest Buy SIG SAUER P320 COMPACT HGA 9MM 3.9IN BBL SIGLITE COYOTE MOD PLY GRIP 3 15RD MAG online SIG SAUER P320 COMPACT HGA 9MM 3.9IN BBL SIGLITE COYOTE MOD PLY GRIP 3 15RD MAG Buy Sig Sauer 320C9BSSMS P320 Compact 9mm Luger 3.90" 15+1 Black Polymer Grip Black Nitron Stainless Steel online Sig Sauer 320C9BSSMS P320 Compact 9mm Luger 3.90" 15+1 Black Polymer Grip Black Nitron Stainless Steel Buy Sight SM17005 3.5-28X30 Thermal Scope Optics Ready online Sight SM17005 3.5-28X30 Thermal Scope Optics Ready Buy Sight SM17004 Thermal Optics Ready 2 16X15 Premium online Sight SM17004 Thermal Optics Ready 2 16X15 Premium Buy Sig Sauer P320 P320 9mm Luger Long Dust Cover 17+1 4.700 Black online Sig Sauer P320 P320 9mm Luger Long Dust Cover 17+1 4.700 Black Buy Sig Sauer P320 P320 9mm Luger 17+1 4.700 Black online Sig Sauer P320 P320 9mm Luger 17+1 4.700 Black Buy Sig Sauer P365X M81 Metal Comp Handgun 9mm Luger 17rd Magazine 3.5 Comp Barrel Metal Grip online Sig Sauer P365X M81 Metal Comp Handgun 9mm Luger 17rd Magazine 3.5 Comp Barrel Metal Grip Buy Sight SM23002 Strikon 1x18 Tactical Optics Ready online Sight SM23002 Strikon 1x18 Tactical Optics Ready Buy Sight SM23001 Strikon VMP 1-4x22 Tactical Optic online Sight SM23001 Strikon VMP 1-4x22 Tactical Optic Buy Sight SM13144CRE 1-10X26 Tactical Optics Ready Scope online Sight SM13144CRE 1-10X26 Tactical Optics Ready Scope Buy Sig Sauer P365 Fuse Semi-automatic Striker Fired Polymer Frame Pistol online Sig Sauer P365 Fuse Semi-automatic Striker Fired Polymer Frame Pistol Buy Sig Sauer MPX Semi-automatic Short Barreled Rifle 9MM 6" Barrel Matte online Sig Sauer MPX Semi-automatic Short Barreled Rifle 9MM 6" Barrel Matte Buy Sig Sauer P365X 380 3.1" Barrel 10-Round Compensator online Sig Sauer P365X 380 3.1" Barrel 10-Round Compensator Buy Sig Sauer P365XF Semi-automatic Striker Fired Polymer Frame Pistol Compact online Sig Sauer P365XF Semi-automatic Striker Fired Polymer Frame Pistol Compact Buy Sig Sauer P365XF Semi-automatic Striker Fired Polymer Frame Pistol Compact online Sig Sauer P365XF Semi-automatic Striker Fired Polymer Frame Pistol Compact Buy Sig Sauer P365XF Semi-automatic Striker Fired Polymer Frame Pistol Compact online Sig Sauer P365XF Semi-automatic Striker Fired Polymer Frame Pistol Compact Buy SIG SAUER 211F-9-GT5-RXSL P211-GT5 9mm 5" Bull Barrel Nitron Semi-Auto Pistol online SIG SAUER 211F-9-GT5-RXSL P211-GT5 9mm 5" Bull Barrel Nitron Semi-Auto Pistol Buy SIG SAUER 211F-9-GT5-COY P211-GT5 9mm 5" Bull Barrel Coyote Cerakote Semi-Auto Pistol online SIG SAUER 211F-9-GT5-COY P211-GT5 9mm 5" Bull Barrel Coyote Cerakote Semi-Auto Pistol Buy SIG SAUER 211F-9-GT5-10 P211-GT5 9mm 5" Bull Barrel Nitron Semi-Auto Pistol online SIG SAUER 211F-9-GT5-10 P211-GT5 9mm 5" Bull Barrel Nitron Semi-Auto Pistol Buy SIG SAUER 211CA-9-GT4-RXSL P211-GT4 9mm 4.2" Bull Barrel Nitron Semi-Auto Pistol online SIG SAUER 211CA-9-GT4-RXSL P211-GT4 9mm 4.2" Bull Barrel Nitron Semi-Auto Pistol Buy SIG SAUER 211CA-9-GT4-COY P211-GT4 9mm 4.2" Bull Barrel Coyote Cerakote Semi-Auto Pistol online SIG SAUER 211CA-9-GT4-COY P211-GT4 9mm 4.2" Bull Barrel Coyote Cerakote Semi-Auto Pistol Buy SIG SAUER 211CA-9-GT4-10 P211-GT4 9mm 4.2" Bull Barrel Nitron Semi-Auto Pistol online SIG SAUER 211CA-9-GT4-10 P211-GT4 9mm 4.2" Bull Barrel Nitron Semi-Auto Pistol Buy SIG SAUER 211F-9-GT5 P211-GT5 9mm 5" Bull Barrel Nitron Semi-Auto Pistol online SIG SAUER 211F-9-GT5 P211-GT5 9mm 5" Bull Barrel Nitron Semi-Auto Pistol Buy SIG SAUER 211CA-9-GT4 P211-GT4 9mm 4.2" Bull Barrel Nitron Semi-Auto Pistol online SIG SAUER 211CA-9-GT4 P211-GT4 9mm 4.2" Bull Barrel Nitron Semi-Auto Pistol Buy Sig Sauer P211 9mm 4.4" Barrel 21/23 Round Capacity online Sig Sauer P211 9mm 4.4" Barrel 21/23 Round Capacity Buy Sig Sauer Barrel 9MM 3.7" Threaded Barrel 1/2X28 Thread Pitch Fits Sig online Sig Sauer Barrel 9MM 3.7" Threaded Barrel 1/2X28 Thread Pitch Fits Sig Buy Sig Sauer Barrel 9MM 3.7" Threaded Barrel 1/2X28 Thread Pitch Fits Sig online Sig Sauer Barrel 9MM 3.7" Threaded Barrel 1/2X28 Thread Pitch Fits Sig

About SI

SI focuses on practical, performance-driven firearm accessories for a wide range of pistols, rifles, and shotguns. Their lineup includes slide adapter plates, latchless charging handles, barrel clamps, compact red dot optics, and dedicated shotgun components, built primarily from aluminum and hardened materials. Products are engineered with attention to fit, function, and ease of installation, aimed at shooters who want reliable upgrades without unnecessary complexity. SI supports competitive, tactical, and recreational shooters by offering parts that address common user needs and enhance firearm ergonomics and capability.

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.

Ready to Shop SI?

Choose SI for straightforward, well-engineered accessories that improve usability and durability without unnecessary complexity....

Browse All Products
Your Data is Protected
256-bit SSL Encryption PCI Compliant Checkout Secure Payment Processing