APEXi N1 EVO Extreme Performance Catback System - 2015-2021 Subaru WRX / STI np-dec-25 Improved Stance: Lowers approximately 1

Improved Stance: Lowers approximately 1

Billetworkz delivers precision-engineered accessories that blend form and function—building on a legacy that began with their foundational shift knobs

including Verus front splitters

supporting and aligning the front and rear sections

APEXi N1 EVO Extreme Performance Catback System - 2015-2021 Subaru WRX / STI np-dec-25 Improved Stance: Lowers approximately 1The APEXi N1 X Evolution Extreme takes the proven performance of the original N1 system and refines it for modern WRX and STI platforms. Designed around a straight through layout for maximum flow, it integrates an internal hybrid silencer that delivers a deep, aggressive tone under throttle with composed resonance during cruising. Each system is finished with lightweight titanium tips that feature a rolled, riveted double pipe diffuser design to