Invidia HS15STIGM4SB Gemini R400 Quad Black Tip Cat-Back 15-21 Subaru WRX/STI

Vehicle Fitment

• 2015-2021 Subaru WRX & Subaru WRX STI (4-door sedan, AWD, 2.0L & 2.5L Turbo)

Features

• Gemini R400 high-flow cat-back exhaust system
• Quad gloss black 101mm stainless steel exhaust tips
• Mandrel-bent 76 mm main piping for improved flow
• SUS304 stainless steel construction for strength and corrosion resistance
• Continuous piping design for reduced back pressure
• Optimized muffler design for a rich, sporty exhaust tone
• Polished CNC-machined flanges and robot TIG welding
• Direct bolt-on installation - no cutting or welding required

Specifications

• Part number: HS15STIGM4SB
• Piping diameter: ~76 mm split to ~60 mm
• Tip diameter: ~101 mm quad tips
• Material: SUS304 stainless steel
• Exit configuration: Quad rear outlets
• Muffler style: Gemini R400 tuned design

Included Components

• 1x Invidia Gemini R400 cat-back exhaust system (HS15STIGM4SB)
• 1x Set of quad gloss black exhaust tips
• Installation hardware (clamps, gaskets, brackets)

Product Description

The Invidia HS15STIGM4SB Gemini R400 Cat-Back Exhaust System is a premium performance upgrade engineered for 2015-2021 Subaru WRX and WRX STI sedans. Built with high-quality SUS304 stainless steel and featuring mandrel-bent piping, this cat-back exhaust improves exhaust gas flow and reduces back pressure compared to the factory system, resulting in enhanced throttle response and torque potential. The Gemini R400 design delivers a rich, aggressive sound that balances daily drivability with performance-oriented audio.

This direct bolt-on system includes a set of eye-catching quad gloss black tips that finish off your WRX or STI's rear aesthetic. Installation uses the vehicle's existing hangers and mounting points, making setup straightforward. Fitment covers 2015-2021 WRX and WRX STI models across applicable turbo engines and AWD drivetrain configurations.